Technical Report for the
La Encantada Silver
Mine
Coahuila State, México
Prepared for
First Majestic Silver Corp.
January 12,
2009
90533
AMENDED AND RESTATED
February 26, 2009
Prepared by
Pincock, Allen &
Holt
Richard Addison, P.E.
Leonel
López, C.P.G.
1.0 TITLE PAGE
This technical report has been prepared in accordance with the National Instrument 43-101 standards of disclosure for mineral projects (NI 43-101) and the contents herein are organized and in compliance with form 43-101F1 contents of the technical report (43-101F1). This technical report is an update of Technical Report Amended for the La Encantada Silver Mine, Coahuila State, México; which was prepared for First Majestic Silver Corp. dated March 19, 2008 and published in SEDAR in March 28, 2008. The first two items are the title page and table of contents that are presented previously in this report and are simply mentioned herein to maintain the specific report outline numbering contained in form 43-101F1 contents of the technical report.
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2.0 TABLE OF CONTENTS
See discussion in Section 1.
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Pincock, Allen & Holt | REVISED | i |
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Pincock, Allen & Holt | REVISED | ii |
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TABLES
Pincock, Allen & Holt | REVISED | iii |
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FIGURES
Pincock, Allen & Holt | REVISED | iv |
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3.0 EXECUTIVE SUMMARY
First Majestic Silver Corp. (FMS) retained Pincock, Allen and Holt (PAH), a division of Australia-based Runge, Inc. to prepare a Technical Report for the silver/lead/zinc deposit of La Encantada Silver Mine located in the Municipality of Ocampo, Coahuila State, and México. This report is an update of Technical Report Amended of March 19, 2008, which was prepared by PAH and published in SEDAR in March 28, 2008. This report is presented to document material change in La Encantada Silver Mine due to an increment of reserves (+183 percent) and resources (measured and indicated -17 percent and inferred +51 percent). This report meets the requirements and is compliant with NI 43-101 and conforms to Form 43-101F1 for technical reports.
La Encantada Silver Mine is owned and operated by Minera La Encantada, S.A. de C.V., wholly-owned Mexican subsidiary of FMS. La Encantada Silver Mine consists of an industrial complex that includes underground silver/lead/zinc mining, a flotation ore processing plant, water wells and pipeline, airport, housing, camp facilities and a new cyanidation plant under construction to process silver tailings. The La Encantada mine was operated by Peñoles for a period of about 25 years, until June 2002. Desmín leased the property from Peñoles and operated the mine and processing plant from July 1, 2004 until November 1, 2006 when Desmín was acquired by FMS. During January to September, 2008 FMS has mined out 178,480 tonnes at an average grade of 297 g/tonne Ag and 2.29 percent Pb.
FMS owns mining rights that cover 2,237 hectares (5,227 acres) within 18 titled concessions and 3 approved claim applications, in addition to 2 other applications under review by the Mines Department. Minera La Encantada has acquired, from the Ejido Tenochtitlán, Municipality of Ocampo, under expropriation regulations, surface land ownership of 1,343 hectares (3,319 acres) where mine, plant, housing, camp and associated facilities are installed. It also owns the surface rights, installations and water rights for two water wells at El Granizo, which supply La Encantada water needs.
Estimated proven and probable reserves and measured and indicated resources for La Encantada, as of September 30, 2008, are presented in Table 3-1. These include proven and probable reserves of 5.2 million tonnes at 208 g/tonne (6.7 oz) Ag, and 2.42 percent (53 lb/tonne) Pb, for a total contained silver equivalent, inclusive of Pb credit, of 35.5 million ounces. These reserves include 4 million tonnes of tailings at an average grade of 168 g/tonne silver, estimated at a Cut-off Grade of 111 g/tonne silver.
La Encantada reserves have been estimated at a Cutoff Grade of 250 g/tonne Ag only and 228 g/tonne Ag equivalent net of Pb credit. The La Encantada proven and probable reserves in hard rock include 1.2 million tones at an average grade of 343 g/tonne silver and 2.39 percent lead.
During the period of January through September, 2008 FMS mined 178,480 tonnes of ore, which included 70,000 tonnes from reserves, in addition of other minerals extracted from different areas of the mine for a total of 108,480 tonnes. To September 30, 2008, the La Encantada exploration programs and underground development increased reserves by approximately 183 percent over the 2007 estimates.
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TABLE 3-1
First Majestic
Silver Corp.
Minera La Encantada, S.A. de
C.V.
La Encantada Mine
Mineral Reserves Prepared by FMS, Reviewed
by PAH as of September 30, 2008 (1)
Total Reserves Proven plus Probable (3) | ||||||||
DEPOSIT | CATEGORY | METRIC TONNES | WIDTH | GRADE | METAL CONTAINED (2) | |||
La Encantada | Reserves | Tonnes | meters | Silver, g/tonne | Lead, % | Zinc, % (4) | Silver (Only) oz. | Silver (Eq) oz. |
Total | Proven | 683,992 | Over 2.00 | 354 | 2.23 | 0.92 | 7,777,602 | 8,261,401 |
Total | Probable | 4,511,686 | Over 2.00 | 186 | 2.45 | 2.54 | 26,936,651 | 27,287,462 |
Total Reserves Proven + Probable | 5,195,677 | Over 2.00 | 208 | 2.42 | 2.33 | 34,714,253 | 35,548,863 | |
Total Resources Measured plus Indicated (3) | ||||||||
TOTAL | Measured | 445,650 | Over 2.00 | 399 | 4.15 | 0.65 | 5,710,055 | 6,025,271 |
TOTAL (5) (6) (7) | Indicated | 4,931,103 | Over 2.00 | 156 | 1.15 | 0.87 | 24,774,263 | 27,082,017 |
Total Resources Measured + Indicated | 5,376,753 | Over 2.00 | 176 | 1.40 | 0.85 | 30,484,318 | 33,107,288 | |
TOTAL PROVEN AND PROBABLE RESERVES PLUS MEASURED AND INDICATED RESOURCES | ||||||||
TOTAL PROVEN PLUS PROBABLE RESERVES AND MEASURED AND INDICATED RESOURCES (8) | 10,572,000 | Over 2.00 | 192 | 1.90 | 1.58 | 65,199,000 | 68,700,000 |
(1) Cut Off Grade estimated as250 g/tonne Ag only;
and 228 g/tonne Ag eq net of Pb credit. Estimated Reserves are exclusive of
Resources.
(2) Silver equivalent includes Pb credit, at
prices US$12.00/oz -Ag, $0.75/lb -Pb. Pb credit=22 g/tonne -Ag.
(3) Mining dilution is included at over 2.00m width. Estimates do not
include mining recovery.
(4) Zinc is not
recovered.
(5) Dump stockpile is considered as measured
resource because the average grade is below COG - 203 g/tonne Ag only and 186
g/tonne Ageq, however with pre-screening may be processed. It requires of
additional testing.
(6) La Morena sulfide deposit
requires additional metallurgical testwork to prove its economic recovery. La
Encantada mill does not have an operating zinc circuit at this
time.
(7) Tailings are included within Indicated
Resources due to required additional testwork and grade below Cutt Off Grade -
111 g/tonne Ag.
(8) Rounded figures.
Total Inferred Resources (1) (2) (3) | ||||||||
Azul y Oro ext. al SW | Inferred | 194,163 | 10.85 | 454 | 0.49 | 0.66 | 2,834,270 | 2,971,423 |
Azul y Oro | Inferred | 97,164 | 2.27 | 434 | 0.93 | 0.38 | 1,355,502 | 1,424,141 |
Dk. San Fco | Inferred | 27,065 | 2.06 | 390 | 8.28 | 2.43 | 339,668 | 358,789 |
Reb 325 | Inferred | 2,196 | 2.03 | 359 | 7.06 | 0.00 | 25,352 | 26,904 |
Buenos Aires | Inferred | 561,824 | 3.40 | 339 | 0.50 | 0.59 | 6,122,831 | 6,519,825 |
San Francisco | Inferred | 186,000 | 2.40 | 304 | 0.64 | 0.14 | 1,818,049 | 1,949,492 |
Sn. Javier. Ext | Inferred | 171,509 | 1.95 | 223 | 4.67 | 3.95 | 1,230,504 | 1,351,736 |
Bonanza | Inferred | 22,000 | 2.77 | 220 | 1.12 | 1.12 | 155,620 | 171,171 |
Breccia San Javier | Inferred | 1,015,000 | Over 2.00 | 105 | 0.57 | 0.78 | 3,426,686 | 4,144,392 |
Intrusivo Milagros | Inferred | 280,000 | 2.00 | 102 | 0.00 | 0.00 | 918,284 | 1,116,274 |
TOTAL (4) (5) | Inferred | 2,557,000 | Over 2.00 | 220 | 1.00 | 1.00 | 18,226,765 | 20,034,145 |
(1) Cut Off Grade estimated as250 g/tonne Ag only;
and 228 g/tonne Ag eq net of Pb credit. Estimated Reserves are exclusive of
Resources.
(2) Silver equivalent includes Pb credit, at prices US$12.00/oz
-Ag, $0.75/lb -Pb. Pb credit=22 g/tonne -Ag.
(3) Mining dilution is included at over 2.00m width. Estimates do not include
mining recovery.
(4) Zinc is not recovered.
(5) Rounded figures.
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These were estimated from the following areas: Breccia Milagros, Azul y Oro, Breccia Keylor, Cuerpo 660 E, Cola de Gallo, Bonanza, La Piedra, Breccia San Javier, Dique San Francisco, San Francisco, Jorobada, Rebaje 141, Rebaje and Ojuela Ampliación zones in addition to the Tailings Dam No. 1. Most of these deposit areas remain opened for exploration and development; for instance, Breccia Milagros appears to represent a significant deposit, the full extent of which is still unknown to FMS.
Measured and indicated resources to September 30, 2008 at La Encantada amount to 5.4 million tonnes at 176 g/tonne (5.7 oz) Ag and 1.40 percent (31 lb/tonne) Pb, for a total contained silver equivalent, inclusive of Pb credit, of about 33.1 million ounces. These resources include 1.6 million tonnes of tailings at an average grade of 76 g/tonne (2.4 oz/tonne). Preliminary testwork appears to indicate amenability and probable economic recovery of silver values from the tailings by cyanide leaching processing. Additional bulk testing is recommended to validate and confirm the resource. These resources represent a decrease of about 17 percent over the resources estimated for 2007 in silver equivalent ounces to 33.1 million, due to upgrade of tailings dam No. 2 to probable reserves.
Additional inferred resources have been estimated by FMS at La Encantada. The inferred resources require additional grade and tonnage information before they may be upgraded to indicated or measured resources. They represent geologic potential to be further investigated. La Encantada has estimated inferred resources that amount to about 2.6 million tonnes at an average grade of 220 g/tonne (7.0 oz/tonne) Ag and 1.0 percent (22 lb/tonne) Pb, for a total estimated content of silver equivalent, inclusive of Pb credit, of about 20.0 million ounces. This estimate represents an increment of 51 percent over the reported resources for 2007.
During the La Encantada 2008 exploration drilling program a new mineralized zone was discovered at the 1790 mine level. This zone has been denominated the Buenos Aires zone and delineated with 15 drill holes resulting in about 536,000 tonnes of Indicated Resources at an average grade of 395 g/tonne Ag (7.2 million ounces of silver equivalent) and 560,000 tonnes of Inferred Resources at an average grade of 339 g/tonne Ag (6.5 million ounces of silver equivalent). Silver equivalent includes Pb credits.
Processing flotation plant facilities have an installed capacity of 800 tonnes per day. It includes all supporting facilities, including laboratory, maintenance, etc. The metallurgical current plant average operating rate is about 800 tonnes per day. About three quarters of the ore comes from the mine and the other quarter from upgraded waste dump rock that has been screened to reject the coarser lower-grade fraction.
FMS is presently building, on a site about 1-1/2 kilometers from the existing flotation plant, a cyandiation plant with a capacity of 3,500 tonnes per day. The plant will process the ore and waste dump rock that is currently processed through the flotation plant in conjunction with reclaimed tailings. The plant is scheduled to commence operation in April 2009. PAH considers the FMS production and cost projections for this operation optimistic, but these parameters will only be clearly established when it has been in operation for six month or more.
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The surface rights to La Encantada Silver Mine are mostly owned by Minera La Encantada (a wholly owned subsidiary of FMS). According to La Encantada, there is a good working relationship with people of the Ejido Tenochtitlán from which the surface rights were purchased by La Encantada, and with the town of Múzquiz, since many of the inhabitants are employed in the exploration or mining operations. No labor or access problems have been reported by La Encantada within the area.
La Encantada was declared in suspension of activities by Peñoles in 2003. In April 24, 2007 La Encantada presented a notification of reactivation of operations at the mine to the National Water Commission (C.N.A.), to SEMARNAT, to Secretaría del Trabajo y Previsión Social, and to PROFEPA. In accordance with legal opinion of October 31, 2008 by Mr. Carlos Galván Pastoriza, La Encantada mining operations are currently and have always been conducted in compliance with all applicable laws and regulations.
PAH is not aware of any environmental liabilities in La Encantada mining district; most of the area covered by La Encantada concessions is mining and prospective land for mineral exploration and mine development. Mr. José Luis Hernández Santibañez, Corporate Manager of Environmental and Permitting for FMS provided PAH with a document dated October 31, 2008 showing the list of Environmental and Operating Permits for La Encantada in current good standing.
PAH believes that La Encantada reserve and resource estimates have been reasonably prepared and conform to acceptable engineering standards for reporting of reserves and resources. PAH believes that the classification of the reserves and resources meets the standards of Canadian National Instrument NI 43-101 and the definitions of the Canadian Institute of Mining, Metallurgy and Petroleum (CIM).
The reserves and resources herein reported by La Encantada were reviewed by PAH and constitute part of an operation by Minera La Encantada, a Mexican subsidiary of FMS. There is no significant technical, legal, environmental, political or other kind of restrictions; therefore, in PAHs opinion, these reserves and resources are exclusive of each category and may not be materially affected by issues that could prevent their extraction and processing.
An economic analysis of La Encantada operation shows positive economics as measured by a cash flow model, and thus the postulated reserve position is accepted. La Encantada Silver Mine shows a net present value of $67 million at a 10 percent discounted rate of return. Table 3-2 presents a summary of
TABLE 3-2
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
Economic Analysis Results as of September 30, 2008
DCFRR, Discount, % | Net Present Value, US $ | |
10 | $ | 44,143,983.00 |
15 | $ | 36,334,243.00 |
20 | $ | 30,019,406.00 |
25 | $ | 24,851,240.00 |
30 | $ | 20,574,641.00 |
TIR: | 85% |
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La Encantada cash flow based on current reserves/resources estimates. Figure 3-1 shows the installations general layout, Figure 3-2 shows the underground mine, and Figure 3-3 shows the mines airstrip.
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4.0 INTRODUCTION
First Majestic Silver Corp. (FMS) retained Pincock, Allen and Holt (PAH) to prepare a Technical Report of exploration activities and results obtained to this date, which represent a material change in the resources and reserves for the silver/lead/zinc deposit of La Encantada Silver Mine located in the Municipality of Ocampo, Coahuila State, México. This report is an update of Technical Report for the La Encantada Silver Mine, Coahuila State, México, prepared for First Majestic Silver Corp. dated March 19, 2008, Amended by Pincock, Allen & Holt, Inc., and was published in SEDAR on March 28, 2008, and it is referred to as Technical Report Amended herein.
The objective of this Technical Report is to provide FMS with a report that will follow existing regulations in Canada. This report presents a material change of the property due a significant increment of reserves including some tailings (+183 percent) and resources (M+I=-17 percent and Inferred=+51 percent) over the estimates reported for 2007. This report meets the requirements and is compliant with NI 43-101 and conforms to Form 43-101F1 for technical reports.
4.1 Qualified Person and Participating Personnel
The principal author of this report is Leonel López, a Certified Professional Geologist (AIPG-CPG-08359), Registered Professional Geologist in the State of Wyoming (PG-2407), a Registered Professional Member of The Society of Mining Engineers (No.1943910) and a PAH Principal Geologist. Mr. López has visited the site during the periods of May 1823, November 1318, 2007 and October 28-31, 2008, to review current status of the property. Mr. López also carried out exploration activities for the La Encantada mine as Peñoles Exploration North Division Manager in the 1980s. Mr. López reviewed available information on the La Encantada mine to update the reported areas where material changes have occurred during the period from July 2007 to September 30, 2008 regarding the mining rights, land tenure, history, environmental concerns, and all aspects of the geology, and reviewed drilling core and results, sampling, data verification and projected resources. Mr. López also reviewed drilling, sampling, volume estimates and location of the two tailings deposits that FMS is preparing for re-processing by cyanidation. Dick Addison reviewed methods and processing plant for La Encantada silver/lead/zinc deposit including research results for cyanidation of the silver tailings and plans for on going construction of a cyanidation plant. Other PAH members collaborated in the review of FMSs tailings deposits modeling to confirm volumes and grade estimates, as well as the reserve estimates, mine planning and safety aspects of the operation.
4.2
Term and Definitions
La Encantada Silver Mine consists of silver/lead/zinc oxidized mineral deposits located in the State of Coahuila, México. La Encantada mine comprises numerous mineral concentrations within the underground development area, including some exhausted deposits and additional geologic potential in other areas. Some of the known deposits within the La Encantada area are the following:
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In this report:
FMS refers to First Majestic Silver Corp.
Desmín refers to Desmín, S.A. de C.V., a wholly-owned subsidiary of FMS.
PAH refers to Pincock, Allen & Holt, Inc., a Division of Runge, Inc., and its representatives.
Peñoles refers to Industrias Peñoles, S.A. de C.V., MET-MEX Peñoles and Grupo Peñoles.
La Encantada Silver Mine refers to the operating underground mine, processing plant and infrastructure facilities that constitute this industrial complex (also referred to as La Encantada mine or La Encantada).
Technical Report for the La Encantada Silver Mine, Coahuila State, México, prepared for First Majestic Silver Corp. dated March 19, 2008, Amended by Pincock, Allen & Holt, Inc., and was published in SEDAR on March 28, 2008, is referred to as Technical Report Amended herein.
Minera La Encantada refers to the operating company and wholly owned subsidiary of First Majestic Silver Corp.
Resource and Reserve definitions are as set forth in the CIM Definitions Standards dated December 15, 2005.
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4.3
Units
All units are carried in metric units, unless otherwise noted. Grades are described in terms of percent (%) or grams per metric tonne (gptonne, g/tonne), with tonnages stated in metric tonnes. Salable metals are described in terms of tonnes, or troy ounces (precious metals) and percent weight.
Unless otherwise stated, Dollars are US Dollars. The following abbreviations are used in this report:
Abbreviation | Unit or Term |
Al2O3 | Alumina |
ANFO | Ammonium nitrate/fuel oil |
ASTM | American Society for Testing and Materials |
Sb | Antimony |
Ag | Silver |
As | Arsenic |
Au | Gold |
Bi | Bismuth |
Cd | Cadmium |
Co | Cobalt |
Cu | Copper |
In | Indium |
Fe | Iron |
g/t | Grams Per Tonne |
kcal | Kilocalories |
kg | Kilograms |
km | Kilometer |
k | Thousands |
Pb | Lead |
LOM | Life of Mine |
Mn | Manganese |
Hg | Mercury |
m | Meters |
masl | Meters Above Sea Level |
mm | Millimeters |
MT | Million Tonnes |
mtpd | Metric tonnes per day |
mtpy | Million tonnes per year |
NPV | Net Present Value |
Ni | Nickel |
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90533 February 26, 2009 |
% | Percent by weight |
Patio | Yard, court or stocking ground |
Se | Selenium |
SiO | Silica |
Sn | Tin |
T or t | Metric Tonne (2,204 lbs), tonne |
Te | Tellurium |
Ti | Titanium |
tpa | Tonnes per annum |
tpy | Tonnes per year |
tpd | Tonnes per day |
ug | Underground |
Wo | Tungsten Oxide |
Zn | Zinc |
$ | United States Dollars |
C$ | Canadian Dollars |
4.4 Source Documents
The source documents for this report are summarized in Section 23.
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90533 February 26, 2009 |
5.0 RELIANCE ON OTHER EXPERTS
This report was prepared for First Majestic Silver Corp. (FMS) by the independent consulting firm Pincock, Allen & Holt, Inc. (PAH) and is based in part on information prepared by other parties. PAH has relied primarily on information provided as part of the following reports, investigations and operating results:
Technical Report for the La Encantada Silver Mine Amended, Coahuila State, México (Technical Report Amended). Prepared for First Majestic Silver Corp. Prepared by Pincock, Allen & Holt, Inc., March 18, 2008, and published in SEDAR on March 28, 2008. | ||
Technical Report for the La Encantada Silver Mine Amended, Coahuila State, México (Technical Report Amended). Prepared for First Majestic Silver Corp. Prepared by Pincock, Allen & Holt, Inc., July 24, 2007, and published in SEDAR on July 25, 2007. | ||
Resource and Reserve Estimates by FMS for La Encantada Silver Mine. Prepared by FMS staff and reviewed by PAH, October 31, 2007 and September 30, 2008. | ||
Resource/Reserve Estimates of the La Encantada Tailings dams No. 1 and 2 based on manual estimations and checked by GEMCOM Geologic modeling. It includes surveying, drilling, cross sections, volumes, tonnage and grade estimates. Prepared by FMS and PAH staff. October and November, 2007 respectively. | ||
Peñoles (Largest Silver producer in the World) information as owner and operator of La Encantada mine for a period of 25 years, including public records, operating reports, geological studies, surveying, sampling data, drilling, geologic modeling and resource estimates, production records and historical reserve estimates as of January 2003. It includes the following reports: | ||
Plan y Programa de Exploración 20012002. Prepared by Ing. Pantaleón Trejo, Manager of Explorations for Mining Operations, Peñoles. June 2002. | ||
Desglose de Mineral Probado y Probable por Cuerpos para 2003. Prepared by: Minera La Encantada, S.A. de C.V., Ing. Pantaleón Trejo, Manager of Explorations for Mining Operations, Peñoles. | ||
Relación de Fundos Mineros Minera La Encantada, S.A. de C.V., Unidad David Contreras. Prepared by Minera La Encantada, Peñoles. Febrero 2007. This report was updated by FMS including additional claims in May 2007. | ||
Database and modeling files for the La Encantada deposits by Peñoles. Provided to FMS in April 2007. |
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90533 February 26, 2009 |
Legal OpinionMinera La Encantada, S.A. de C.V., a wholly owned subsidiary of First Majestic Silver Corp. Legal Opinion by Durango-based office of legal advisers, by Mr. Carlos Galván Pastoriza, Abogado, prepared on October 31, 2008. | ||
Geochemical and Isotopic Study of Calcite Stockworks at La Encantada Mining District; Relationships with Orebodies and Implications for Exploration. A Thesis submitted to the Faculty of the Department of Mining and Geological Engineering, at the University of Arizona at Tucson, in partial fulfillment of the requirements for the degree of Master of Science with a Major in Geological Engineering. By: Raúl Díaz-Unzueta, 1987. | ||
Evaluación Geológica Unidad Minera La Encantada, Municipio de Ocampo, Coahuila, México. Prepared by: Exploraciones Geológico-Mineras de Occidente, S.A. de C.V. Septiembre 2006. | ||
Geologic Evaluation of the La Encantada Property, State of Coahuila de Zaragoza, México. Prepared by: J.N. Helsen, Ph.D., P. Geo. December 2006. | ||
Data provided by Desmín, S.A. de C.V. as operator of La Encantada under lease from Peñoles, July 1, 2004 to November 1, 2006. | ||
Information provided by FMS as owner and operator of La Encantada Silver Mine, including the period from November 2006 to May 2007. | ||
Information provided by FMSs Corporate Manager of Environmental and Permitting, Ing. José Luis Hernández Santibañez, on notifications of mining activities resumption at La Encantada mine and current status of operating permits to: | ||
Delegado Federal de la SEMARNAT, Estado de Coahuila. April 24, 2007. | ||
Delegado Federal de la STPS (Secretaría de Trabajo y Previsión Social) in the State of Coahuila. April 24, 2007. | ||
Director Local de CNA (Comisión Nacional del Agua), Estado de Coahuila. April 24, 2007. | ||
Delegado Federal de la PROFEPA (Procuraduría Federal de Protección al Ambiente), Estado de Coahuila. April 24, 2007. | ||
PAH observations on site visit during the periods of May 18-23, November 11 18, 2007 and October 28-31, 2008. |
PAH believes that this information is reliable for use in this report. PAH has reviewed ownership documents for the purchase of Minera La Encantada shares from Peñoles; acquisition of Desmín shares; purchase land rights under expropriation procedure where La Encantada mine, plant, camp and ancillary installations are located; and documents for sampling and applications for renewal of the Permiso Ambiental Unico (environmental permit for operating); as well as copies of the titled concessions for La Encantada mining rights.
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This information was also reviewed by FMS legal advisers and a legal opinion was provided to PAH by the Durango City-based legal firm of Mr. Carlos Galván Pastoriza in a document issued on October 31, 2008. Therefore, PAH believes all above described documents and information regarding the property current status, legal title and environmental compliance for La Encantada miningmetallurgical operation to be accurate and current in legal standing.
Pincock, Allen & Holt | REVISED | 5.3 |
90533 February 26, 2009 |
6.0 PROPERTY DESCRIPTION AND LOCATION
Additional details are presented in Technical Report Amended for La Encantada Silver Mine of March 18, and published in SEDAR on March 28, 2008. Figure 6-1 is a General Location Map and Figure 6-2 is a Mining Concessions Map.
6.1 Property Description
This Technical Report presents an update of La Encantadas current operating conditions and projections as planned by FMS.
La Encantada Silver Mine property modifications for the period of October, 2007 to September, 30 2008 include the following:
Successful exploration programs have delineated a significant increment of reserves, including some tailings (+183 percent) and resources (M+I - -17 percent and Inf. +51 percent) for 2008 over 2007, at the La Encantada Silver Mine.
The La Encantada mining rights cover 2,237 hectares (5,227 acres) within 21 Mining Concessions including 3 approved Applications which have been accepted by the Dirección General de Minas and are now under the process of registration at the Mines Department (1,250 hectares or 3,089 acres). Two other Concession Applications have presented at the Mines Department and are under review for approval. These Concession Applications cover additional lands within the surrounding area of La Encantada for further protection and exploration potential. No other changes have occurred in total land coverage at La Encantada Silver Mine.
All the Mining Concessions legal status was provided by legal opinion, dated October 31, 2008 from the Durango City-based firm of Mr. Carlos Galván Pastoriza, legal advisers for FMS in México. PAH also requested and received an updated review by legal advisers of the mining concessions current status showing that all mining claims owned by Minera La Encantada, S.A. de C.V. are current in meeting the legal obligations and requirements by Mexican Mining and Environmental Laws and Regulations including assessment works, property taxes and operating permits for the period that covers to December 31, 2008. Table 6-1 shows the List of Mining Concessions at La Encantada.
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TABLE 6-1
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
List of Mining Concessions
No. | Name | Title No. | Surface Ha. |
1 | Encantada | 143,943 | 75.0000 |
2 | El Pajarito | 167,061 | 9.0000 |
3 | Montecarlo | 167,062 | 9.0000 |
4 | El Tigre | 167,065 | 41.0000 |
5 | El Camello | 167,066 | 75.0000 |
6 | Los Angeles | 167,067 | 20.0000 |
7 | Ampliación de Los Angeles | 167,068 | 27.2300 |
8 | El Granizo | 167,069 | 25.0000 |
9 | La Presita | 167,070 | 25.0000 |
10 | Regalado | 167,071 | 100.0000 |
11 | El Golpe 10 | 178,385 | 40.0000 |
12 | Rosita No. 19 | 189,752 | 79.9525 |
13 | Los Angelitos | 189,758 | 27.2300 |
14 | Los Angelitos 2 | 189,759 | 27.2300 |
15 | Los Angelitos 3 | 190,341 | 16.0000 |
16 | La Presita 10 | 194,878 | 100.0000 |
17 | San Javier | 217,855 | 3.0227 |
18 | Las Rositas | 227,288 | 287.0000 |
19 | Rosita 1* | 232,026 | 50.0000 |
20 | Rosita 2* | 232,028 | 350.0000 |
21 | Rosita 3* | 232,027 | 850.0000 |
22 | Platón (1) | 07 / 16718 | 3,000.0000 |
23 | Fracción Platón (2) | 07 / 16718 | 0.0000 |
TOTAL COVERAGE | 2,236.6652 |
(*) Application approved in process of registration.
(1) Mining Application in process. Final coverage will be defined
when the Title is issued. Area NOT INCLUDED.
(2) Fraction of Platón is included in the Paltón claim.
It will be Titled with different No.
Pincock, Allen & Holt | REVISED | 6.2 |
90533 February 26, 2009 |
7.0 |
ACCESSIBILITY, CLIMATE, LOCAL RESOURCES, INFRASTRUCTURE AND PHYSIOGRAPHY |
La Encantada Silver Mine is located within an isolated mining district in northern México. It is located in the northern part of the physiographic province of the Sierra Madre Oriental in the NW portion of the State of Coahuila. It is located in the municipality of Ocampo, at about 120km to the N60ºW from the city of Múzquiz, and 120km to the N7ºW from the city of Ocampo, Coahuila.
UTM coordinates for La Encantada area are as follows: N3,139,550; E739,660.
La Encantada mining district consists of two main silver/lead underground mines, the La Encantada and the El Plomo mines. Both of these mine areas have been consolidated into one operation, which is now owned and operated by FMS. Figure 7-1 shows the El Plomo inactive camp.
Additional details on Accessibility, Infrastructure, Climate, Vegetation, Physiography, Hydrology and Local Resources are presented in Technical Report Amended.
Pincock, Allen & Holt | REVISED | 7.1 |
90533 February 26, 2009 |
8.0 HISTORY
In 2003 Peñoles reported proven and probable reserves at the closing of La Encantada mine including 485,000 tonnes at an average grade of 570 g/t Ag and 3.98 percent Pb. FMSs exploration efforts are directed to explore other areas of interest within the extensive underground workings, validate these historical figures and advance development of additional exploration targets. By June 2007, FMS reported NI 43-101 proven and probable reserves of 633,000 tonnes at an average grade of 315 g/tonne Ag, in addition to measured and indicated resources of 1.4 million tonnes at an average grade of 276 g/tonne Ag, and about 1.5 Million tonnes of inferred resources at an average grade of 200 g/tonne Ag, in Technical Report Amended of July 24, 2007 published in SEDAR.
The La Encantada aggressive exploration and development investments during 2007 resulted in additional proven and probable reserves estimated at 1.2 million tonnes for 2008 at an average grade of 343 g/tonne (11.03 oz/t) and measured and indicated resources estimated at 9.4 million tonnes at an average grade of 173 g/tonne (5.6 oz/t), in addition to inferred resources estimated at 2.6 million tonnes at a grade of about 220 g/tonne (7.0 oz/t). The 2008 reserves and resources represent a significant increment over the 2007 reported reserves (+183 percent) and resources of (M+I -17 and inferred +51 percent). Proven and probable reserves plus measured and indicated resources contain approximately 68.7 million ounces of silver equivalent, while inferred resources may contain about 20.0 million ounces of silver equivalent.
From the period of October, 2007 to September, 2008, FMS has mined and processed 178,480 tonnes of ore from La Encantada Silver mine at an average recovered grade of 297 g/tonne (9.5 oz/tonne) Ag, for a total of 1,704,300 contained ounces. FMSs 2008 production consisted of about 70,000 tonnes of ore from the proven and probable reserves, in addition to ore extracted from different newly discovered areas during mine preparation and development activities, for a total of 108,480 tonnes. Currently the plant is operating at an average rate of about 800 tonnes per day, while the mine continues to access, prepare new working phases and develop additional reserves and resources.
Pincock, Allen & Holt | REVISED | 8.1 |
90533 February 26, 2009 |
9.0 GEOLOGICAL SETTING
Please refer to Technical Reports Amended dated July 24, 2007 and March 19, 2008 which were published respectively on July 25, 2007 and in March 28, 2008 in SEDAR.
To this date, there are no changes to report regarding the La Encantada Silver Mine geology.
National Instrument 43-101 Standards of Disclosure for Mineral Projects. Form 43-101F1 Technical ReportInstructions (5), December 23, 2005.
Figure 9-1 shows the La Encantada Regional Geologic Map.
Figure 9-2 shows La Encantada Silver Mine Geologic Cross Section.
Pincock, Allen & Holt | REVISED | 9.1 |
90533 February 26, 2009 |
10.0 DEPOSIT TYPES
There are no changes to report regarding geologic and mineral deposit concepts for the La Encantada Silver Mine.
Please refer to Technical Report Amended dated July 24, and published in SEDAR on July 25, 2007.
Figure 10-1 shows Types of Mineral Deposits at La Encantada.
Pincock, Allen & Holt | REVISED | 10.1 |
90533 February 26, 2009 |
11.0 MINERALIZATION
For details on mineralization at La Encantada Silver Mine please refer to Technical Report Amended of July 24 and published in SEDAR on July 25, 2007.
No changes regarding mineralization characteristics of the La Encantada Silver Mine have occurred since last publication in Technical Report Amended. However, the mineralized zones of the La Encantada mine have been further increased by discovery of a new mineralized zone denominated Buenos Aires.
FMS exploration drilling program to investigate the Azul y Oro deposit resulted in interception of an unknown mineralized zone which comprises a series of NW-SE oriented veins and mineralized breccia zones containing high grade silver mineralization with lead and zinc. These structures show variable widths of up to eight meters. The Buenos Aires zone is located between the Azul y Oro and La Escalera breccia zones within the northeastern portion of the mine.
Currently known projections of the Buenos Aires zone have been drilled from the mine levels 1870, 1790 and 1635. Preliminary drilling has determined some blocks of indicated and inferred resources which enclose approximately 850,000 tonnes containing some estimated 13 million ounces of silver equivalent in oxides.
FMS is preparing underground access to the zone and additional drilling to upgrade the Buenos Aires resource base.
Figure 11-1 shows Duplicate Channel Sample at Breccia San Javier.
Figure 11-2 shows stope 274 High Grade Silver at Breccia San Javier.
Figure 11-3 shows the Stope 141 El Chamaco High Grade zone at the Bonanza Dike.
Figure 11-4 shows Breccia Milagros mineralization.
Pincock, Allen & Holt | REVISED | 11.1 |
90533 February 26, 2009 |
12.0 EXPLORATION
12.1 Introduction
La Encantada Silver Mine has been subjected to exploration programs from its discovery in the 1950s, by prospectors in the early stages and by Peñoles since the late 1960s to 2003. FMS has developed an aggressive program of explorations including mine development and preparations for drilling from underground sites. Additional diamond drilling is planned from surface locations, as well as geophysical surveying to investigate areas of interest and confirm other previously identified exploration areas.
Exploration efforts carried out during the second half of 2007 through 2008 were primarily focused in proving and developing additional reserves and resources for La Encantada mine. These resulted in a significant increment of both resources and reserves. Major efforts were developed in the areas of Breccia Milagros, Bonanza, San Francisco, Intrusivo Milagros, Azul y Oro, and Cuerpo de Zinc at mine level N-1535 and in the sampling of the old dumps. A long term exploration program was initiated to investigate the promising target at the La Escalera breccia zone. A new exploration target was identified during the course of explorations to define the Azul y Oro mineralized zone. The newly discovered zone, denominated Buenos Aires, is located between the Azul y Oro and the La Escalera breccia zones. FMS exploration efforts have resulted in a material change of the La Encantada reserve/resource base. These results, in addition to some tailings, show an increment of about 183 percent in proven and probable Reserves and a decrement of about 17 percent in measured and indicated resources over previously reported reserves and resources of October 31, 2007. Additional inferred resources have resulted in an increment of about 51 percent. These results have increased the ounces of silver equivalent contained for the La Encantada mine to about 69 million in proven and probable reserves plus measured and indicated resources. Additional exploration may upgrade the inferred resources, currently estimated at about 20 million ounces of silver equivalent.
Sampling of old dumps was also advanced and about 150,000 tonnes of screened material was measured, sampled and indicated during the period, in addition to screening and processing about 42,000 tonnes. Screening recovery of the dumps is about 40 percent in tonnage and grade enrichment from about 120 g/tonne Ag to about 160 g/tonne Ag. Figure 12-1 shows the La Encantada Exploration Program.
12.2 Exploration Programs
FMSs program of underground exploration was designed to investigate the Milagros and San Javier breccia zones, as well as the San Francisco bedded deposits and the Bonanza area where numerous veins occur associated with the Bonanza dike. The La Escalera breccia zone appears to be a significant target for exploration.
Pincock, Allen & Holt | REVISED | 12.1 |
90533 February 26, 2009 |
During the period of September 2007, to September 30, 2008, a total of about 6,660 meters of core drilling was completed. During the period of January to June, 2008 underground workings for exploration purposes were developed at the La Encantada mine, including about 1,490 meters of access ramps, drifts, and crosscuts, and about 850 meters of exploration tunneling for drill sites access. This development resulted in a significant increment of resources and reserves at the various mine levels of the La Encantada Silver Mine, within the Stope 141, Stope 325, Breccia Milagros, Bonanza, Dique San Francisco, San Francisco, Jorobada, San Javier Extensión and Alto del Dique La Escondida areas.
12.2.1 Geophysical
Exploration
FMS has designed an extensive 2008 program of exploration based on geophysical surveying to investigate the various identified anomaly areas, and to confirm other indicated potential zones. This program was completed during the period of January to October, 2008, and includes about 50 km of lines to be measured by Natural Source Audio-frequency Magnetotelluric methods (NSAMT). Readings were carried out along lines at 100m and 50m spacing according to geologic conditions, at 25m and 50m stations along the lines. This geophysical method takes reading of resistivity and conductivity parameters. The survey was conducted by Zonge Engineering and Research Organization from Tucson, Arizona. The Report is in progress. Some exploration targets have been identified and confirmed from previous research, including the most outstanding targets for investigation, such as the El Plomo, La Escalera Breccia zone and the Anomalous areas A, B, C and D. Figure 12-2 shows Geophysical Anomaly A Line 3. Figure 12-3 shows Geophysical Anomaly El Plomo Line 4.
12.2.2 Geochemical Exploration
No geochemical sampling has taken place at La Encantada during 2008; however, FMS has designed a 2009 exploration program that includes sampling for geochemical investigations in the areas of the geophysical anomalies. This program is estimated to include about 500 samples.
12.3 Drilling
Drilling programs at La Encantada have been limited since the best exploration results may have been obtained through underground development. Additionally, topographic conditions at the mine and irregular morphology of mineral concentrations make it difficult to plan for drilling. Therefore, drilling from underground sites and mine workings has proven to be the most effective combination for exploration at La Encantada.
During the period from September, 2007 to September 30, 2008, the La Encantada exploration team completed drilling from underground sites totaling 6,660 meters to investigate continuity and depth of the Azul y Oro, Breccia San Javier, and La Escalera mineralized structures. These drill holes resulted in discovery of the Buenos Aires mineralized zone, extension and confirmation of some of San Francisco and Azul y Oro mineralized zones.
Pincock, Allen & Holt | REVISED | 12.3 |
90533 February 26, 2009 |
Additional drilling was developed at the old Peñoles tailings dams to determine volume and grade of the two tailings dams. Metallurgical testwork was carried out in some of the drilled tailings. Grade, tonnage and metallurgical recovery estimates have resulted in additional resources for the La Encantada Silver Mine, since some of the silver contained by the tailings appears to be amenable for economic recovery by Cyanide Leaching processing methods. The tailings drilling program included 15 drill holes totaling 168 meters at the Tailings Dam No. 1, and 34 drill holes for a total drilled depth of 576 meters in Tailings Dam No. 2. Trenches and surveying delimited additional tailings volume at the Presa No. 3. Figure 12-4 shows tailing samples.
12.3.1 Exploration Drilling
FMS exploration activities for La Encantada mine include three drill rigs for drilling from underground sites. The program completed during 2008, consisted of a total underground development of 2,340m including drifts, crosscuts, raises, ramps and stopes development in addition to 5,000m of development carried out during the second semester of 2007. Numerous drill sites have been prepared during 2008.
Details of the exploration program developed and completed during 2008 are included in Table 12-1. This program resulted in a material change with significant additional Resources for the La Encantada mine. Table 12-1 shows the exploration program completed during 2008.
TABLE 12-1
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
Completed Exploration Program for the Period November, 2007 to September,
2008
Exploration Activities | Objective | Area | Total Development |
Underground Development | Access ramps, drifts, crosscuts, raises, drill sites, etc | Access to La Escalera, Brccia Milagros, Azul y Oro, Bonanza, Jsan Javier, etc | 6,144 meters |
Underground Drilling | Exploration, Resource Blocks upgrade, investigate extension zones, etc | Azaul y Oro, La Escalera, Bonanza, San Javier, etc | 6,660 meters |
Geophysics | Confirm previously defined anomalies |
La Encantada coverage | Approximately 50km of geophysical lines |
The FMS exploration program for La Encantada includes an aggressive underground and drilling plan that has a high probability of success given the geological conditions of the mineralization at the mine. In PAHs opinion the combination of direct exploration methods, drilling and underground development represents a good balance for exploration at La Encantada. The program is directed to access projected known areas of mineralization as well as to investigate other adjacent and new promising areas that may result in an increment of the resource base and a higher level of reserves for the mine. This has been proven positive during the period of 2008 since the new Buenos Aires zone was discovered and resulted in additional resources containing approximately 13 million ounces of silver equivalent.
Pincock, Allen & Holt | REVISED | 12.6 |
90533 February 26, 2009 |
The exploration program suggested by FMS for the La Encantada Silver Mine for implementation during the period of calendar year 2009 is presented in Table 22-1 including estimated costs. This program consists of 7,195 meters of drilling, including 23 drill holes from underground sites, and 10,807 meters of underground drifting. Table 12-2 shows the La Encantada exploration program for 2009.
TABLE 12-2
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
Exploration Program for the Period October-December, 2008, January-September,
2009
Exploration Activities | Objective | Area | Total Development |
Underground Drilling | Explore extensions, confirm and delineate Resource blocks | Azul y Oro, Buenos Aires, La Escalera, Cedrito, Bonanza, Falla María Isabel | 23 DH - 7,195 meters |
Underground Development | Crosscuts, drifts, ramps and drill sites | 1790 Mine Level, Buenos Aires zone, San Francisco, Bonanza and Azul y Oro | 11,807 meters |
In PAHs opinion, FMSs exploration program at La Encantada represents an aggressive exploration program with a high probability of success to upgrade the mines reserve and resource base, and with high probability for discovery of additional mineralized zones, which would lengthen the mines life. PAH recommends implementation of the suggested program at an estimated cost of about $2.5 million.
Pincock, Allen & Holt | REVISED | 12.8 |
90533 February 26, 2009 |
13.0 DRILLING
FMS continued with an aggressive drilling program at La Encantada during the period from September, 2007 to September, 2008. FMS has three drilling rigs to carry out the exploration drilling from underground sites. FMSs program for 2009 includes 7,195 meters of core drilling from underground sites to investigate the La Escalera breccia, Buenos Aires and Azul y Oro targets from the 1870, 1970 and 1535 mine levels. Exploration drilling requires access and drill site preparation, which for the underground exploration is estimated to be approximately 10,800 meters of ramps, drifts, crosscuts and drill site construction.
During the period of January through September 2008, drilling at La Encantada completed 29 drill holes for a total depth of 6,660 meters from underground locations. This program resulted in additional total estimated tonnage of 850,000 tonnes of indicated and inferred resources at an average grade of about 340 g/tonne (about 11 oz/tonne) Ag in oxides mineralization with lead and zinc.
Fifteen drill holes were completed from underground access to investigate the Azul y Oro mineralized structure. These drill holes also intercepted a new mineralized zone denominated Buenos Aires. Some of these drill holes intersected some of the mineralized structures of the Azul y Oro zone confirming geologic continuity of the mineralization. Additional resource and some reserve blocks were confirmed by the program. Figure 13-1 shows the Buenos Aires Drilling and Figure 13-2 shows Underground Drilling for Azul y Oro and Buenos Aires zones.
Details of FMSs 2008 and 2009 drilling program are presented in Tables 12-1 and Table 12-2. Estimated costs for the 2009 program are presented in Table 22-1.
FMS has defined future targets of exploration for drilling from surface. These include confirmation of geophysical and structural anomalies, such as:
Exploration drilling from underground drill sites includes:
Pincock, Allen & Holt | REVISED | 13.1 |
90533 February 26, 2009 |
PAH believes that this drilling program from surface and underground workings, in combination with underground development, is appropriate and well designed to explore promising targets. Geologic potential exists to discover additional mineralized zones along the development workings. Estimated budget for this program is included in Section 22 of this Report - Recommendations. PAH recommends implementation of this program. Figure 13-3 shows Buenos Aires Drill Core Intercept. Figure 13-4 shows Buenos Aires High Grade Core.
Pincock, Allen & Holt | REVISED | 13.4 |
90533 February 26, 2009 |
14.0 SAMPLING METHOD AND APPROACH
PAH reviewed La Encantadas sampling program for the preparation of the Technical Report Amended dated July 24, 2007. Full description of sampling method and approach by La Encantadas geologic crews is presented in the Technical Report Amended July 24, 2007. Additionally, PAH also reviewed the La Encantada sampling procedures for this Technical Report and did not notice changes in protocols that may affect the results, other than improving in some areas, such as QA/QC with increasing number of filed duplicates for drilling and reserve blocks samples.
The samples are brought into the La Encantada laboratory for preparation and assaying. Duplicate samples are sent to Inspectorate Lab for assay checks. Additional representative samples are sent to the La Encantada laboratory for density determinations. For the period of 2008 FMS has assayed 38 duplicate samples and 26 pulp samples at Inspectorate Lab in Reno, Nevada for comparison with assay results from the La Encantada lab. A total of 28 representative samples for density were sent to the La Encantada Lab from the El Plomo, Bonanza, Breccia Milagros, San Javier and San Francisco zones.
In PAHs opinion, the channel and core sampling and methods applied by La Encantada exploration and mining crews is done carefully and responsibility by well trained samplers. The sampling appears to reconcile with silver/lead head assays for the processing plant, as well as with production and sales by Minera La Encantada. The channel and core samples appear to properly represent the mineralization of La Encantada various deposits; therefore, they are acceptable for resource and reserve estimates. Figure 14-1 shows channel sampling. Figure 14-2 shows a channel sample of Azul y Oro Veinlet. Figure 14-3 shows a channel Sample of Azul y Oro at Level 1790.
Pincock, Allen & Holt | REVISED | 14.1 |
90533 February 26, 2009 |
15.0 SAMPLE PREPARATION, ANALYSIS AND SECURITY
15.1 Sample Preparation
PAH reviewed the La Encantada sample preparation for the Technical Report Amended dated March 18, 2008. FMS has not modified the sample preparation methods and procedures. Details are presented in the Technical Report Amended.
15.2 Laboratory Facilities
PAH notes that the La Encantada laboratories generally appear to be adequate, with reasonable cleaning and organization. The laboratory currently conducts about 800 samples by fire assay and AA per month, including exploration samples, development samples, and mill samples.
More details on laboratory facilities are presented in Technical Report Amended of July 24, 2007.
FMSs procedure for quality controls is by sending drill core, mine samples and/or pulps to an outside laboratory, usually Inspectorate Labs in Reno, Nevada. Samples of concentrates are regularly sent to Peñoles for check assays. The laboratory duplicates pulp assays at about 1 sample for every 20 and it includes field duplicates, standard samples and introduction of blank samples.
15.3 Check Assaying
To evaluate sample quality control, the La Encantada personnel perform periodic check analyses on samples. For the period from November, 2007 to September, 2008, La Encantada has sent 64 samples to Inspectorate Laboratories, an independent commercial laboratory in Reno, Nevada for duplicate analysis. These include 38 channel samples from reserve blocks in addition to 26 core duplicates of pulps from the reserve blocks. Results of the assays and graphs are presented in the following tables and graphs. La Encantada Silver Mine is mining and processing mineralization contained in oxides, which presents highly variable metal concentrations due to its inherent genetic characteristics. In this type of mineral occurrence, the comparison of assays may present high variations, depending on the mineral content of each sample. High grade silver assays may present differences of up to 80 percent due probably to some nugget effect, while the middle range grade samples usually result in close assays. In overall comparison, however, within a range of assays that represent very low to very high grades, the correlation is acceptable at an average of 74 percent for silver, and 100 percent for lead. While the duplicates of pulp samples show a better correlation of 99 percent for silver and 98 percent for lead.
Tables 15-1, 15-2 and Figures 15-1 and 15-2 show the assay results and graphs for samples of the La Encantada reserve blocks as duplicate samples and as duplicate pulp samples. The comparison is between assays by the La Encantada mines lab and Inspectorate Laboratories. Figure 15-3 shows the Buenos Aires drill core.
Pincock, Allen & Holt | REVISED | 15.1 |
90533 February 26, 2009 |
TABLE 15-1
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
Sample Assay Checks
Reserve Duplicate Samples
(1)
INSPECTORATE LAB | LA ENCANTADA LAB | Sample Type | ||||||||
DUPLICATE SAMPLES | DUPLICATE SAMPLES | |||||||||
Sample No. | Ag gr/tonne | Pb % | Fe % | Zn % | Sample No. | Ag gr/tonne | Pb % | Fe % | Zn % | |
143348 | 0 | 0.01 | 0.01 | 0.80 | 146541 | 0 | 0.15 | 2.13 | 0.01 | BNO. 790-ESC-2 |
143349 | 0 | 0.00 | 0.00 | 0.41 | 146552 | 0 | 0.11 | 9.00 | 0.02 | BNO. 790-ESC-2 |
146012 | 26 | 0.01 | 0.91 | 12.70 | 146373 | 30 | 0.08 | 13.68 | 0.82 | SN FCO. 641 |
146013 | 363 | 1.45 | 0.43 | 8.90 | 146384 | 350 | 1.18 | 11.83 | 0.53 | SN FCO. 641 |
146014 | 334 | 20.50 | 0.09 | 26.80 | 146395 | 310 | 23.94 | 32.91 | 0.11 | SN FCO. 660 |
146015 | 36 | 1.27 | 0.09 | 41.30 | 146949 | 60 | 0.91 | 41.67 | 0.08 | SN FCO. 660 |
146016 | 71 | 2.55 | 0.16 | 42.20 | 146960 | 40 | 3.20 | 47.88 | 0.11 | SN FCO. 660 |
146044 | 32 | 0.07 | 0.14 | 0.78 | 146595 | 30 | 0.23 | 1.15 | 0.04 | BNO. 790-8 |
146045 | 5 | 0.09 | 0.03 | 3.48 | 143379 | 0 | 0.18 | 0.79 | 0.09 | BNO. 790-8 |
146046 | 6 | 0.04 | 0.13 | 0.47 | 140038 | 120 | 0.32 | 4.71 | 0.29 | BNO. 790-8 |
146047 | 18 | 0.01 | 0.05 | 0.41 | 143396 | 0 | 0.10 | 0.65 | 0.02 | BNO. 790-8 |
147901 | 9 | 0.02 | 0.08 | 0.54 | 147811 | 0 | 0.28 | 1.45 | 0.09 | BNO. 790-9 |
147902 | 3 | 0.01 | 0.05 | 0.38 | 147822 | 0 | 0.09 | 0.99 | 0.02 | BNO. 790-9 |
147903 | 102 | 0.06 | 0.18 | 0.32 | 147833 | 120 | 0.08 | 0.63 | 0.12 | BNO. 790-9 |
147904 | 727 | 0.56 | 0.65 | 4.40 | 147844 | 880 | 0.34 | 6.88 | 0.69 | BNO. 790-9 |
147905 | 3 | 0.02 | 0.01 | 0.19 | 147855 | 290 | 0.70 | 2.49 | 0.46 | BNO. 790-9 |
147906 | 703 | 0.11 | 0.28 | 0.85 | 147866 | 710 | 0.17 | 1.58 | 0.20 | BNO. 790-9 |
147907 | 4 | 0.01 | 0.03 | 0.22 | 147877 | 50 | 0.24 | 6.24 | 0.19 | BNO. 790-9 |
147908 | 226 | 0.22 | 0.45 | 1.21 | 147899 | 150 | 1.00 | 0.00 | 0.17 | BNO. 790-10 |
147919 | 6 | 0.02 | 0.04 | 0.40 | 148920 | 0 | 0.10 | 0.85 | 0.02 | BNO. 790-9 |
147920 | 36 | 0.02 | 0.02 | 0.19 | 148930 | 0 | 0.06 | 0.39 | 0.00 | BNO. 790-9 |
147921 | 1 | 0.01 | 0.01 | 0.20 | 148940 | 0 | 0.08 | 0.69 | 0.01 | BNO. 790-9 |
147922 | 21 | 0.03 | 0.22 | 0.85 | 148954 | 0 | 0.05 | 1.10 | 0.07 | BNO. 790-12 |
147923 | 1 | 0.01 | 0.02 | 0.21 | 148965 | 0 | 0.04 | 0.56 | 0.01 | BNO. 790-12 |
147924 | 2 | 0.01 | 0.00 | 0.10 | 148976 | 0 | 0.06 | 0.51 | 0.01 | BNO. 790-12 |
147925 | 3 | 0.02 | 0.09 | 0.94 | 148987 | 0 | 0.07 | 1.52 | 0.00 | BNO. 790-12 |
147926 | 2 | 0.01 | 0.02 | 0.32 | 148998 | 0 | 0.38 | 3.05 | 0.00 | BNO. 790-12 |
147927 | 7 | 0.02 | 0.13 | 0.78 | 148710 | 0 | 0.10 | 1.00 | 0.00 | BNO. 790-12 |
147928 | 10 | 0.01 | 0.05 | 0.40 | 148721 | 10 | 0.11 | 1.06 | 0.01 | BNO. 790-12 |
147929 | 3 | 0.01 | 0.01 | 0.19 | 148732 | 0 | 0.07 | 0.52 | 0.00 | BNO. 790-12 |
147930 | 1 | 0.01 | 0.02 | 0.16 | 148753 | 130 | 0.07 | 1.88 | 0.01 | BNO. 790-13 |
147931 | 128 | 0.18 | 0.55 | 1.73 | 148764 | 120 | 0.28 | 3.67 | 0.37 | BNO. 790-13 |
147932 | 1,155 | 0.06 | 0.85 | 3.72 | 148775 | 930 | 0.09 | 4.82 | 0.58 | BNO. 790-13 |
147934 | 1,409 | 0.48 | 2.05 | 6.78 | 148786 | 350 | 0.11 | 9.18 | 0.13 | BNO. 790-13 |
147935 | 137 | 0.10 | 0.59 | 1.97 | 148797 | 790 | 0.73 | 15.98 | 1.85 | BNO. 790-13 |
147936 | 15 | 0.01 | 0.03 | 0.16 | 149208 | 110 | 0.14 | 13.10 | 0.70 | BNO. 790-13 |
147937 | 11 | 0.01 | 0.04 | 0.36 | 149219 | 0 | 0.09 | 0.29 | 0.01 | BNO. 790-13 |
147938 | 2 | 0.01 | 0.02 | 0.15 | 149230 | 0 | 0.10 | 0.95 | 0.01 | BNO. 790-13 |
Min. | 0.20 | 0.00 | 0.00 | 0.10 | 0.00 | 0.04 | 0.00 | 0.00 | ||
Max | 1,409 | 21 | 2 | 42 | 930 | 24 | 48 | 2 | ||
Average | 148 | 1 | 0 | 4 | 147 | 1 | 7 | 0 | ||
Stdev. | 323 | 3 | 0 | 10 | 259 | 4 | 11 | 0 | ||
Correlation. | 0.74 | 1.00 | 0.11 | 0.03 |
(1) Data by FMS, formatted by PAH
Pincock, Allen & Holt | REVISED | 15.2 |
90533 February 26, 2009 |
TABLE 15-2
First Majestic Silver Corp.
Minera
La Encantada, S.A. de C.V.
La Encantada Silver Mine
Sample
Assay Checks
Reserve Duplicate of Pulp Samples (1)
INSPECTORATE LAB | LA ENCANTADA LAB | Sample Type | ||||||
PULP SAMPLES | PULP SAMPLES | |||||||
Sample No. | Ag gr/tonne | Pb % | Zn % | Sample No. | Ag gr/tonne | Pb % | Zn % | |
143379 | 8 | 0.06 | 0.21 | 143379 | 0 | 0.18 | 0.09 | BNO. 790-8 |
143396 | 23 | 0.02 | 0.05 | 143396 | 0 | 0.10 | 0.02 | BNO. 790-8 |
146341 | 1 | 0.01 | 0.01 | 146341 | 20 | 0.09 | 0.02 | AyO N-850 |
146373 | 31 | 0.07 | 0.91 | 146373 | 30 | 0.08 | 0.82 | SN FCO. 641 |
146384 | 408 | 1.65 | 0.71 | 146384 | 350 | 1.18 | 0.53 | SN FCO. 641 |
146552 | 1 | 0.01 | 0.00 | 146552 | 0 | 0.11 | 0.02 | BNO. 790-ESC-2 |
146595 | 18 | 0.15 | 0.08 | 146595 | 30 | 0.23 | 0.04 | BNO. 790-8 |
146949 | 30 | 0.95 | 0.12 | 146949 | 60 | 0.91 | 0.08 | SN FCO. 660 |
146960 | 55 | 3.15 | 0.16 | 146960 | 40 | 3.20 | 0.11 | SN FCO. 660 |
147811 | 26 | 0.03 | 0.22 | 147811 | 0 | 0.28 | 0.09 | BNO. 790-9 |
147822 | 4 | 0.03 | 0.04 | 147822 | 0 | 0.09 | 0.02 | BNO. 790-9 |
147833 | 170 | 0.10 | 0.22 | 147833 | 120 | 0.08 | 0.12 | BNO. 790-9 |
147844 | 781 | 0.37 | 0.80 | 147844 | 880 | 0.34 | 0.69 | BNO. 790-9 |
143379 | 8 | 0.06 | 0.21 | 143379 | 0 | 0.18 | 0.09 | Channel |
143396 | 23 | 0.02 | 0.05 | 143396 | 0 | 0.10 | 0.02 | Channel |
146341 | 1 | 0.01 | 0.01 | 146341 | 20 | 0.09 | 0.02 | Channel |
146373 | 31 | 0.07 | 0.91 | 146373 | 30 | 0.08 | 0.82 | Channel |
146384 | 408 | 1.65 | 0.71 | 146384 | 350 | 1.18 | 0.53 | Channel |
146552 | 1 | 0.01 | 0.00 | 146552 | 0 | 0.11 | 0.02 | Channel |
146595 | 18 | 0.15 | 0.08 | 146595 | 30 | 0.23 | 0.04 | Channel |
146949 | 30 | 0.95 | 0.12 | 146949 | 60 | 0.91 | 0.08 | Channel |
146960 | 55 | 3.15 | 0.16 | 146960 | 40 | 3.20 | 0.11 | Channel |
147811 | 26 | 0.03 | 0.22 | 147811 | 0 | 0.28 | 0.09 | Channel |
147822 | 4 | 0.03 | 0.04 | 147822 | 0 | 0.09 | 0.02 | Channel |
147833 | 170 | 0.10 | 0.22 | 147833 | 120 | 0.08 | 0.12 | Channel |
147844 | 781 | 0.37 | 0.80 | 147844 | 880 | 0.34 | 0.69 | Channel |
Min. | 0.70 | 0.01 | 0.00 | 0.00 | 0.08 | 0.02 | ||
Max. | 781 | 3 | 0.91 | 880 | 3.20 | 0.82 | ||
Average | 120 | 1 | 0.27 | 118 | 0.53 | 0.20 | ||
Stdev. | 224 | 1 | 0.31 | 243 | 0.86 | 0.27 | ||
Correlation | 0.99 | 0.98 | 0.99 |
(1) Data by FMS, formatted by PAH.
Pincock, Allen & Holt | REVISED | 15.3 |
90533 February 26, 2009 |
The reserve duplicate samples mineral content range includes assays that vary from 0.2 to 1,409 g/tonne Ag. The average correlation coefficient of the silver grades is acceptable for the set of samples, at 74 percent, with slightly lower assays by the La Encantada lab. The reserve pulp duplicate samples, for the set of duplicate samples, range in silver values from 0.7 to 781 g/tonne Ag with an average correlation of 99 percent and slightly lower silver assays for the La Encantada Lab and average correlation of 98 and 99 percent respectively for lead and zinc. Therefore, pulp duplicate samples assays show good sample preparation procedures at La Encantada. PAH believes that the reproducibility of silver grades is acceptable, and it represents acceptable procedures and practices in the sampling preparation processes.
La Encantada Silver Mine has implemented a strict program of Quality Control by introduction of blank and standard samples, as well as the insertion of field duplicate samples and pulp duplicates to keep a close control of the assay results. PAH recommends continuing with current sample preparation and shipping processes, which show acceptable differences in assay checks.
15.4 Conclusion
Overall, PAH found that the results from the check assaying are excellent and acceptable for pulp duplicates, the mineralization in oxides may cause larger differences in assays due to its nature. It is PAHs opinion that the sample methods and analyses are representative of the deposits at La Encantada mine, and that most of La Encantadas data was generated by procedures that were carried out according to accepted industry standards using accepted practices.
PAH finds that the exploration, sampling, and laboratory analysis for La Encantada operation is being conducted by FMS in a reasonable manner consistent with standard industry practices. In PAHs opinion the sampling results appear to be reasonably representative of the deposits mineralization and believes that they may be used with acceptable confidence in the estimation of the mineable reserves.
Pincock, Allen & Holt | REVISED | 15.7 |
90533 February 26, 2009 |
16.0 DATA VERIFICATION
PAH has not taken independent samples from the surface or underground exposures of the mineral concentrations at La Encantada mine, as other Qualified Persons have previously sampled the mineralization as discussed in this report, and the production records are the most reliable data of mineralization contained in the ore deposits under development at the mine. Peñoles developed and operated La Encantada mine for over 25 years producing over 80 million ounces of silver. Peñoles is one of the leading Mexican mining companies and the worlds largest silver producer.
FMS has established in a short operating period a systematic procedure to verify data and quality control which is proving effective and accurate. Assay data and information generated by the operation is transmitted manually; however, the entire paper trail is accessible and available for inspection.
FMS initiated effective control of La Encantada operations since November 2006 when it took control of the mining operation. La Encantada has established an active program of assay checks for samples and pulps of exploration, production and concentrates at the mines lab in comparison to assays performed by Inspectorate Laboratories of Durango city and Reno, Nevada, and concentrate sampling and assaying program by a sales representative in the city of Torreón, Coahuila to check the assays reported by the MET-MEX Peñoles smelter.
Table 16-1 presents a summary of concentrate assays for July, 2008 of shipments to MET-MEX Peñoles. This summary presents a comparison of assays by La Encantada lab and MetMex Peñoles.
TABLE 16-1
First Majestic Silver
Corp.
Minera la Encantada, S.A. de C.V.
La Encantada Silver
Mine
Concentrate Checks for July, 2008 Shipments
Concentrates | First Majestic Silver Corp. | Met Mex Peñoles SA de CV | |||||||||
Shipment | Date | Weight | Assays | Content | Weight | Assays | Content | ||||
No. | (Tonnes) | Silver | lead | Silver | Lead | Tonnes | Silver | Lead | Silver | Lead | |
Kg/tonne | % | Kg | Tonnes | Kg/tonne | % | Kg | Tonnes | ||||
DES- 2008 - 101 | 7/1/2008 | 31.80 | 10.57 | 39.37 | 336.12 | 12.52 | 32.71 | 11.438 | 37.42 | 374.15 | 12.24 |
DES- 2008 - 102 | 7/4/2008 | 30.57 | 9.87 | 39.94 | 301.71 | 12.21 | 30.98 | 10.318 | 34.08 | 319.66 | 10.56 |
DES- 2008 - 103 | 7/7/2008 | 32.82 | 9.50 | 31.16 | 311.80 | 10.23 | 33.53 | 9.582 | 29.65 | 321.25 | 9.94 |
DES- 2008 - 104 | 7/9/2008 | 22.81 | 7.90 | 28.63 | 180.20 | 6.53 | 23.42 | 8.453 | 24.69 | 197.97 | 5.78 |
DES- 2008 - 105 | 7/10/2008 | 32.88 | 6.95 | 27.08 | 228.50 | 8.90 | 33.37 | 7.29 | 23.65 | 243.38 | 7.89 |
DES- 2008 - 106 | 7/13/2008 | 31.83 | 7.32 | 27.44 | 233.01 | 8.73 | 32.89 | 7.53 | 25.71 | 247.68 | 8.46 |
DES- 2008 - 107 | 7/15/2008 | 32.54 | 6.95 | 24.31 | 226.16 | 7.91 | 32.52 | 6.85 | 22.28 | 222.62 | 7.25 |
DES- 2008 - 108 | 7/17/2008 | 31.39 | 6.00 | 13.73 | 188.19 | 4.31 | 31.96 | 5.99 | 20.58 | 191.38 | 6.58 |
DES- 2008 - 109 | 7/18/2008 | 32.73 | 5.39 | 24.41 | 176.43 | 7.99 | 32.59 | 5.30 | 17.72 | 172.81 | 5.77 |
DES- 2008 - 110 | 7/21/2008 | 30.15 | 7.35 | 16.84 | 221.57 | 5.08 | 30.80 | 7.74 | 16.75 | 238.21 | 5.16 |
DES- 2008 - 111 | 7/23/2008 | 30.66 | 5.15 | 18.63 | 157.89 | 5.71 | 31.35 | 5.34 | 18.14 | 167.48 | 5.69 |
DES- 2008 - 112 | 7/27/2008 | 30.19 | 4.88 | 11.82 | 147.32 | 3.57 | 30.70 | 5.09 | 11.50 | 156.16 | 3.53 |
DES- 2008 - 113 | 7/29/2008 | 31.28 | 4.95 | 11.69 | 154.83 | 3.66 | 31.84 | 4.96 | 11.48 | 157.85 | 3.66 |
DES- 2008 - 114 | 7/29/2008 | 30.30 | 5.79 | 16.19 | 175.44 | 4.91 | 30.93 | 5.91 | 16.31 | 182.64 | 5.04 |
Total | 432 | 7.036 | 331 | 3,039 | 102 | 440 | 101.779 | 310 | 3,193 | 98 | |
Average | 31 | 0.503 | 24 | 31 | 7.270 | 22 | |||||
Max | 33 | 10.570 | 40 | 34 | 11.438 | 37 | |||||
Min | 23 | 4.880 | 12 | 23 | 4.957 | 11 | |||||
Correlation | 0.99 | 1.00 | 0.95 |
Pincock, Allen & Holt | REVISED | 16.1 |
90533 February 26, 2009 |
The coefficient of correlation is excellent for all determinations, including weight (99 percent), silver (100 percent) and lead (95 percent).
Figure 16-1 shows correlation between silver assays of both laboratories.
PAH believes that an adequate amount of checking has been conducted and that the results are representative of the mineralization and concentrates produced at La Encantada and shipped to the smelter.
PAHs conclusion is that the results from check assaying are reasonable, including appropriate preparation procedures that the sampling results appear to be reasonably representative of the deposit mineralization and concentrates, and should be usable with acceptable confidence in the estimation of the mineable reserves.
Pincock, Allen & Holt | REVISED | 16.2 |
90533 February 26, 2009 |
17.0 ADJACENT PROPERTIES
No adjacent properties exist within the surrounding area of La Encantada. The El Plomo mine was operated as an independent mine for a period of time during the early stages of La Encantada development; however, in 1983 it was purchased by Minera La Encantada and it has been part of La Encantada mine since then. Underground developments of La Encantada and El Plomo were connected and established as one underground system. No other mine exists nearby the La Encantada area.
La Encantada mine is located at about 100km from the cities of Ocampo and Muzquiz, in Coahuila, México.
La Encantada mine housing facilities include 180 single family houses, events center, hotel and three restaurants, elementary school facilities, secondary school by teleconferences, sport facilities for soccer, squash and bowling, apart from the administration offices and warehouses, etc. Refurbishing of required facilities is in progress.
FMS has consolidated ownership of the La Encantada mine area by acquiring all mining claims and additional concessions around the property. Surface rights have also been acquired by La Encantada from the local Ejido (land community) under expropriation proceedings in accordance with the Mining Laws.
Pincock, Allen & Holt | REVISED | 17.1 |
90533 February 26, 2009 |
18.0 METALLURGICAL TESTING AND MINERAL PROCESSING
The ore processed at La Encantada is a complex mixture of oxide and sulfide minerals and is consequently difficult to process efficiently. The principal economic minerals are as follows:
The gangue is principally limestone and hematite with minor amounts of quartz, manganese, and zinc.
The ore is relatively soft and friable making for easy crushing and grinding. The ore processing method consists of crushing and grinding followed by two sequential flotation steps, the first consists of sulfide mineral flotation and the second is oxide mineral flotation. The reason for floating the ore in two stages is because the reagents used for oxide flotation are detrimental to sulfide flotation. Recoveries are poor, a reflection of the difficult mineralogy of the rock.
A cyanide leach plant is currently under construction at La Encantada and plans are to place it in operation in April 2009. The plant will process ore from the mine and waste dumps and from the three existing tailings containments: No. 1, No. 2 and No. 3.
Metallurgical testwork has been conducted on cyanide leaching of old tailings and of flotation concentrate. Results of the testwork are presented in Table 18-1 and 18-2, respectively.
Table 18-1 shows that cyanide leaching achieves relatively good recovery, averaging 59 percent, from the lower-grade, lower-tonnage No. 1 Tailings, and relatively poor recovery, averaging 40 percent, from the higher-grade, higher-tonnage No. 2 Tailings. Recovery from the composite sample, a mixture of fresh ore and Tailings No. 1 and No. 2, was good at 67 percent, though the sample is not particularly representative of what will be fed to the plant.
Table 18-2 shows that cyanide leaching of one sample of flotation concentrate gave very good recovery, at 98 percent. When the cyanide leach plant becomes operational, one option for the future plans is to eliminate flotation and instead, cyanide leach the ore and waste dump rock in the new plant following crushing and grinding in the existing mill. Direct cyanide leaching the ore and waste dump rock is projected to be 78 percent in the FMS Cash Flow Model, which appears reasonable based on the results of leaching concentrate and old tailings; however, the testwork is limited but the results were comfirmed with historic testworks made by Penoles.
One area of concern in the cyanide leaching plant is that the process water used at La Encantada is slightly saline and testwork conducted thus far has been with standard potable water. It may well be that the use of plant process water will be of no consequence but, until this is tested, this uncertainty remains.
Pincock, Allen & Holt | REVISED | 18.1 |
90533 February 26, 2009 |
TABLE 18-1
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
Cyanide Leach Testwork, Tailings and Ore/Tailings Composite
Parameter | Units | Jales 1 | Jales 2 | Composite* |
FMS Cash Flow Model | ||||
Resource | tonnes | 900,375 | 4,015,711 | |
Silver Grade | grams/tonne | 72 | 168 | 187 |
Projected Recovery | percent | 52 | 48 | 59 |
Laboratory Results | ||||
Silver Grade | ||||
June 22, 2007 | grams/tonne | 89 | 163 | |
July 12, 2008 | grams/tonne | 163 | 231 | |
March 14, 2008 | grams/tonne | 103 | 104 | |
Cyanide Consumption | ||||
June 22, 2007 | grams/tonne | |||
July 12, 2008 | grams/tonne | 4.3 | 4.0 | |
March 14, 2008 | grams/tonne | 3.3 | 3.4 | |
Silver Recovery | ||||
June 22, 2007 | percent | 59 | 43 | |
July 12, 2008 | percent | 46 | 67 | |
March 14, 2008 | percent | 59 | 31 | |
Average | percent | 59 | 40 |
* Made up of 37.5% mine ore, 31.25% Tailings No. 1, and 31.25% Tailings No. 2
TABLE 18-2
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
Cyanide Leach Testwork, Flotation Concentrate
Parameter | Units | Value |
Head Grade | ||
Silver | grams/tonne | 9,350 |
Lead | percent | 35.13 |
Zinc | percent | 1.77 |
Iron | percent | 6.65 |
Manganese | percent | 0.44 |
Test Conditions | ||
Weight of sample | kilograms | 13 |
Cyanide additon | grams | 699.2 |
Lime adition | grams | 132.8 |
Water addition | liters | 26 |
Cyanide strength | grams/liter | 27 |
pH | 11.5 | |
Slurry density | weight percent | 33 |
Leach time | hours | 24 |
Test Results * | ||
Cyanide addition rate | kilograms/tonne | 54 |
Lime addition rate | kilograms/tonne | 10 |
Silver recovery | percent | 97.53 |
*Note: Residual concentrations of cyanide and lime
could not be determined because of the strong yellow
color of the leach solution.
Pincock, Allen & Holt | REVISED | 18.2 |
90533 February 26, 2009 |
19.0 MINERAL RESOURCE AND MINERAL RESERVE ESTIMATES
La Encantada uses conventional, manual methods, assisted by computer databases, to calculate the tonnage and average grades of the mineral resources and reserves. FMS has initiated the compilation of all data to incorporate it into a database and create a geologic model in SURPAC software which has been acquired by the company. FMS has reviewed and calculated resources and reserves for La Encantada to assess the current status of the property and to use it as a basis for future updated estimates. FMS assumed control of La Encantada Silver Mine operation from November 2006. FMS estimated the first resource/reserve base for the La Encantada mine as of May 31, 2007. This estimate is an update of October 31, 2007, resource/reserve base and it incorporates exploration and underground development results for the mine. During the current period, November, 2007 to September 2008, La Encantada mined a total of about 205,000 tonnes of ore, from which only 90,000 tonnes were mined out of the previously reported reserves and also increased the reserves during the period to about 5.2 million tones, including 4.0 million tones of tailings to be processed by cyanidation. This resource/reserve update calculation has been estimated as of September 30, 2008.
19.1 Introduction
FMS estimated proven and probable reserves, as of October 31, 2007, amounted to 1.2 million tonnes at an average grade of 312 g/tonne Ag and 1.77 percent Pb. Cutoff grade was estimated as 256 g/tonne Ag only, and 241 g/tonne Ag equivalent net of Pb credit. The estimated reserves were included in the deposits of: Breccia Milagros, Azul y Oro, Breccia Keylor, Cuerpo 660, Mantos 314, Chicotón Stope, San Francisco, La Piedra, Cola Gallo deposits and some dumps.
FMS has implemented exploration programs based on drifting, drilling and channel sampling. During this reported period, October, 2007 through September 2008, FMS has increased the silver contained in the resource/reserve base for the La Encantada mine by about 31 percent including proven and probable reserves and measured and indicated resources. Additional inferred resources have been delineated and other exploration targets are under further investigations. Additional resources and reserves were developed within the La Encantada mine in the Breccia Milagros, Bonanza, San Francisco, Azul y Oro and Jorobada deposits. A new discovery was made during the drilling program of the Azul y Oro deposit, the Buenos Aires deposit, which has been currently estimated in additional resources for La Encantada in excess of 536,000 tonnes of Indicated Resources at an average grade of 395 g/tonne Ag (7.2 million ounces of silver equivalent) and 560,000 tonnes of Inferred Resources at an average grade of 339 g/tonne Ag (6.5 million ounces of silver equivalent). Silver equivalent includes Pb credits. Dump materials and tailings dams have been sampled and measured resulting in additional reserves and resources for the La Encantada mine.
19.2 Methodology
Under the La Encantada mines diverse geologic environment, the resource and reserve blocks have been defined at the various drift levels where sampling has found mineable ore within the mineralized zones.
Pincock, Allen & Holt | REVISED | 19.1 |
90533 February 26, 2009 |
The reserve tonnage and grade are based largely on channel samples along drifts, crosscuts and other mine workings. Drilling from underground sites was initiated to explore the San Francisco, Breccia Milagros, San Javier and Azul y Oro mineralized structures to depth. This program was completed with 29 drill holes and a total depth of 6,660 meters. FMSs surface drilling program has been on hold due to delay in delivery of geophysical exploration program report.
Reserve and resource blocks range in length according to variable extensions of breccia or mineralized zones, and are from 50 to 150 meters in length along the mineralized structures. The resource and reserve blocks are developed by drifting across breccia zones and structures. Proven reserve blocks are projected up to 15 meters from the drift in which the channel samples were taken, and Probable blocks extending another 25 meters beyond the proven blocks where the geology and mine developments may allow.
All adits, drifts ramps and access development headings are regularly surveyed by La Encantada staff. The mineralized zones are subdivided into vertical sections through the multiple horizontal levels, such that each vertical section has 10 meter horizontal separation from the immediately adjacent sections. For reserve estimation, the cross sectional area of mineralization is drawn on each of these 10 meter spaced sections using Auto CAD software and the assayed sample lengths. The volume of mineralization on each section is calculated for the mineralized zone extending 5 meters on either side of the section. The density factor (specific gravity) is then input into the calculation, and tonnage is calculated based on the formula; Length (in meters) X Width (in meters) X Height (in meters) X Specific Gravity = tonnes of material.
The density factor used to convert reserve block volumes into tonnes has been determined as a weighted average from ore samples representative of the various deposit areas. The density tests were performed by Peñoles and by FMS. Numerous samples have been sent to an external lab (Inspectorate Lab) for determination. Currently FMS has carried out density tests of representative samples of the different deposits within the mine. Breccia Milagros samples density determinations have reported an average of 2.98, El Plomo area (3.07), Bonanza (3.14), San Javier (2.75) and Dique San Francisco (2.96) . La Encantada continues to follow a conservative approach by taking an average density of 2.70.
PAH believes that, on average, the density for mineralization is reasonable. PAH recommends that additional representative samples be taken periodically, as checks for bulk density determination, to ensure and properly adjust the application of an appropriate density factor as required.
To estimate the average grade and thickness for each 10 meter section that crosses a reserve block, La Encantada composites all the sample grades in the drift that occur within 5 meters on either side of the section. La Encantada has determined that the most appropriate filter for grade outliers is to assign a top grade of 1,000 g/tonne Ag to those samples. The total length of samples in the composite is then divided by the total number of composites, giving the average width of the mineralization in the drift at that section. Similarly, the average silver grade of the samples, weighted by length, gives the average silver grade for the drift at that section.
Pincock, Allen & Holt | REVISED | 19.2 |
90533 February 26, 2009 |
The tonnes and grade for each reserve block are then determined by combining the tonnes and grade results obtained for each 10 meter section that crosses the block. The resource block tonnes and grade are tabulated by La Encantada personnel on a series of spreadsheet summaries.
PAH notes that the sampling conducted across the mineralized zones for use in the reserve estimates is done with cutoff grade and width considerations, at a minimum mining width of 2.00m. This minimum width typically includes zones within the structures that are above the cutoff grade, as well as sub-ore grade mineralization below the cutoff grade, in which case La Encantada eliminates these areas when possible.
PAH also notes that in a few local areas, the drift is wholly enclosed by the mineralized structures and, unless there are some additional crosscuts or drilling, the vein width is taken as that measured across the confines of the drift opening. PAH recommends that the true structure widths, measured by cross cuts and/or the drill holes, be used as much as possible in the blocks of reserve and resource estimation.
The reserve blocks estimated by La Encantada are exclusive of the resource blocks.
In PAHs opinion the reserve and resource block estimates carried out by La Encantada have been reasonably prepared and conform to acceptable engineering standards for reporting of reserves.
19.3 Cutoff Grade Calculations
PAH has used more conservative metal prices than those used by First Majestic, mainly because most pricing used by the company is much higher than current international pricing levels, and PAH has chosen more conservative pricing in view of the current international economic trends. PAHs prices are about 13.4 percent lower than First Majestics prices. A comparison of metals prices is shown in Table 19-1.
TABLE 19-1
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada
Silver Mine
Comparison of Metal Prices for 43-101 (U.S. Dlls)
Commodity |
First Majestic Average Prices |
3-Year Rolling Average Prices |
Average October 2008 Prices |
PAH Prices |
Gold ($/oz.) Silver ($/oz.) Lead ($/lb.) Zinc ($/lb.) |
$699 $12.70 $0.90 $0.85 |
$708 $13.23 $0.90 $1.28 |
$807 $10.44 $0.67 $0.57 |
$708 $12.00 *$0.75 *$0.50 |
*PAH lead and zinc prices in line with current pricing and predicted trends
19.3.1 Underground Mine Cut-Off Grade
For the current reserve, PAH has calculated breakeven cutoff grades for both the underground mine operations and also the dump recovery program. The basic parameters applicable to the cutoff grade calculations for the underground mine are shown in the following Table 19-2 and Tables 25-13 and 25-14 in Section 25.8.2 of this report.
Pincock, Allen & Holt | REVISED | 19.3 |
90533 February 26, 2009 |
TABLE 19-2
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
*Cutoff Grade Parameters (U/G Mine Only)
Concepts | Costs and Other |
Average Total Operating Cost Per Tonne | $55.01 |
COG Silver only (g/t Ag) | 250 |
COG - With Lead Credits (g/t Ag) | 228 |
Totall Milled in Period (Jan-Sep, 2008) | 136,326 |
Silver Recovery in Mill (%) | 60% |
Payable Silver from Smelter | 95% |
Payable Lead from Smelter | 90% |
Gold Price ($/oz.) | $708 |
Silver Price ($/oz.) | $12.00 |
Lead Price ($/lb.) | $0.75 |
Zinc Price ($/lb.) | $0.50 |
Monetary Exchange Rate | $12.50 pesos: $1.00 |
*Based on January-September, 2008 Operating Data
Equating the parameters in the above table (U/G mine only), the breakeven cutoff grade for silver (CAg), based solely on silver for total operating costs (Table 25-13) and process recoveries anticipated is as follows:
CMAg =Total operating costs/ (silver price X mill recovery X smelter payable metal)
CMAg= $55.01/( $12.00 X 0.60 X 0.95) = 8.04 oz Ag per tonne or 250 g Ag/t.
However, there is a lead contribution for La Encantada ores. Production of lead in the concentrates from the mine only throughSeptember 2008 is about 777.5 tonnes. The calculation for lead contribution is as follows:
Revenues for Mine from lead (Rm) = Lbs lead in concentrates X payable from smelter X lead price:
Rm =777.5 t X 2204.6 lbs/t X 0.90 X $0.75
Rm = $1,157,002
Rm/ tonnes mined & milled = $1,157,002/ 136,326 t = $8.49/t
The silver equivalent of lead contribution = $8.49 /$12.00 = 0.71 oz Ag/t or 22 g Ag/t.
Pincock, Allen & Holt | REVISED | 19.4 |
90533 February 26, 2009 |
The adjusted mine cutoff grade (CMAg) is then: 250 g Ag/t -22 g Ag/t = Ag = 228 g Ag/t.
19.3.2 Mine Dump Recovery Cutoff Grade
The basic parameters used for the cutoff grade calculations for the recovery of dump material are shown in Table 19-3 as follows:
TABLE 19-3
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
*Cutoff Grade Parameters (Mine Dump Recovery)
Concepts | Costs and Other |
Average Total Operating Cost Per Tonne | $40.98 |
COG Silver only (g/t Ag) | 203 |
COG - With Lead Credits (g/t Ag) | 184 |
Total Milled in Period (Jan-Sep, 2008) | 42,155 |
Silver Recovery in Mill (%) | 55% |
Payable Silver from Smelter | 95% |
Payable Lead from Smelter | 90% |
Gold Price ($/oz.) | $708 |
Silver Price ($/oz.) | $12.00 |
Lead Price ($/lb.) | $0.75 |
Zinc Price ($/lb.) | $0.50 |
Monetary Exchange Rate | $12.50 pesos: $1.00 |
*Based on January-September 2008 Operating Data
Equating these parameters (dumps only), the breakeven cutoff grade for mining and processing of the in-situ dumps, based solely on silver for the total operating costs (Table 25-14) and process recoveries anticipated, is as follows:
CDAg = Total Operating Costs/ (silver price X mill recovery X smelter payable metal).
CDAg= $40.98/ ($12.00 X 0.55 X 0.95) = 6.54 oz Ag/t or 203 g Ag/t.
A lead contribution is also applicable for recovery of dump material. About
183 tonnes of lead in concentrates have been produced through September2008. The calculation for the lead contribution is as follows:
Revenues for lead from Dumps (Rd)= Lbs in concentrates X payable from smelter X lead price:
Rd = 183 tonnes X 2204.6 lbs/t X 0.90 X $0.75
Rd= $272,323
Pincock, Allen & Holt | REVISED | 19.5 |
90533 February 26, 2009 |
Rd per tonne of dumps processed = $272,323/42,155 = $6.46/t.
Ag Equivalent per tonne = Rd/ Ag price = $6.46/ $12.00 = 0.54 oz Ag/t or 17 g Ag/t.
Adjusted Cut-off Grade (CDAg) for dumps = 203 g Ag/t 17Ag/t = 186 g Ag/t.
19.3.3 Tailings Recovery Cutoff Grade
First Majestic is constructing a new 3,500-tpd processing plant, principally for the recovery of silver values from the flotation tailings. This plant will employ a grinding circuit with thickeners, counter-current decantation and a Merrill-Crowe metals recovery system. PAH has calculated a breakeven cutoff grade for the recovery of silver from the tailings, based on the parameters such as plant recoveries and operating costs set forth in First Majestics metallurgical test-work reports, and that First Majestic will send silver-gold precipitates to La Parrilla unit, where bullion bars will be produced. The basic parameters used for the Tailings Recovery cutoff grade estimation are shown in Table 19-4.
TABLE 19-4
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
*Cutoff Grade Parameters (Tailings Recovery)
Concepts | Costs and Other |
Average Total Operating Cost Per Tonne | $17.00 |
COG Silver only (g/t Ag) | 111 |
**Total Milled in Period (Jan-Sep, 2008) | 0 |
Silver Recovery in New Plant (%) | 40% |
Payable Silver from Refinery | 99.5% |
Gold Price ($/oz.) | $708 |
Silver Price ($/oz.) | $12.00 |
Lead Price ($/lb.) | $0.75 |
Zinc Price ($/lb.) | $0.50 |
Monetary Exchange Rate | $12.50 pesos: $1.00 |
*Based on FM Metallurgical Data & Cost
Estimates
**Plant throughput design is 3,500 tpd
The cutoff grade for the tailings is calculated with the formula:
CTAgt= Total Operating Costs/(Plant recovery X silver price X payable metal)
CTAg = $17.00/(0.40 X $12.00 X 0.995)
CtAg= 3.56 oz Ag/t or 111 g Ag/t
Pincock, Allen & Holt | REVISED | 19.6 |
90533 February 26, 2009 |
19.4 Reserve Estimates
PAH has reviewed La Encantada reserve update of September 30, 2008 along with factors for mining dilution and recovery. In addition, the sampling methods, assaying procedures, compositing methods, data handling, cutoff grade application and grade calculations were reviewed. Several reserve blocks were cross-checked to track data handling from the initial assays to the final tonnage and grade calculation to ensure that the stated methods and practices were observed.
La Encantada has estimated mineable Reserves for the following deposits:
The total in-situ diluted hard rock Reserve at a minimum mining width of 2.00m, as reviewed by PAH, is 1.209 million tonnes averaging 343 grams (11 oz) per tonne silver and 2.39 percent (53 lb/tonne) lead, for a total of 13.9 million contained ounces of silver net of lead credit. Additional reserves were estimated from Tailings Dam No. 1, which contains about 4.0 million tones at an average grade of 168 g/tonne (5.4 oz/tonne) silver at estimated at a Cutoff Grade of 111 g/tonne silver, to be reprocessed by cyanidation. As discussed previously in the calculation methodology section, the proven ore category has been projected up to 15 meters from the drift sample data, while the probable ore category is projected another 15 meters beyond the proven ore.
La Encantada has been processing pre-screened dump materials. Results for the month of September 2008 indicate that screened dumps yield about 40 percent of tonnage with increased silver grade from about 67 g/tonne to about 131 g/tonne; therefore, the dump materials have been included as an indicated resource due to silver content of an average grade below the cutoff grade. Estimated recovered screened tonnage from the measured dumps is about 225,000 tonnes. Table 19-5 presents a summary of La Encantada proven and probable reserves. Figure 19-1 shows Buenos Aires resource blocks. Figure 19-2 shows Breccia Milagros reserves. Figure 19-3 shows Azul y Oro resource blocks. Figure 19-4 shows San Francisco Dike reserve blocks.
Pincock, Allen & Holt | REVISED | 19.7 |
90533 February 26, 2009 |
TABLE 19-5
First Majestic
Silver Corp.
Minera La Encantada, S.A. de
C.V.
La Encantada Mine
Mineral Reserves Prepared by FMS, Reviewd
by PAH as of September 30, 2008 (1)
Total Proven Reserves (3) | ||||||||
DEPOSIT | CATEGORY | METRIC TONNES | WIDTH | GRADE | METAL CONTAINED (2) | |||
La Encantada | Reserves | meters | Silver, g/tonne | Lead, % | Zinc, % (4) | Silver (Only) oz. | Silver (Eq) oz. | |
Reb 141 | Proven | 3,127 | 1.50 | 1,733 | 18.48 | 2.66 | 174,217 | 176,429 |
Breccia Keylor | Proven | 9,753 | 3.41 | 1,254 | 4.66 | 3.44 | 393,185 | 400,083 |
Ojuelas Amp | Proven | 4,919 | 1.67 | 598 | 8.87 | 4.09 | 94,651 | 98,131 |
Azul y Oro | Proven | 77,979 | 2.41 | 417 | 0.90 | 0.47 | 1,046,648 | 1,101,804 |
Reb 325 (DK Milagros) | Proven | 4,291 | 2.16 | 380 | 2.62 | 0.04 | 52,384 | 55,420 |
San Francisco | Proven | 72,483 | 2.26 | 369 | 1.09 | 0.33 | 859,911 | 911,179 |
Dk. San Fco | Proven | 10,181 | 1.78 | 329 | 3.65 | 3.05 | 107,616 | 114,817 |
Breccia Milagros | Proven | 358,253 | Variable > 2.00 | 322 | 1.52 | 0.94 | 3,705,006 | 3,958,404 |
La Piedra | Proven | 5,988 | 2.84 | 301 | 3.41 | 2.32 | 57,993 | 62,229 |
Cola Gallo | Proven | 3,928 | 4.66 | 296 | 5.56 | 0.00 | 37,376 | 40,154 |
Cuerpo 660 E | Proven | 124,962 | 2.00 | 292 | 4.75 | 0.99 | 1,173,145 | 1,261,533 |
Bonanza | Proven | 8,128 | 2.40 | 289 | 0.48 | 0.27 | 75,468 | 81,217 |
TOTAL | Proven | 683,992 | Over 2.00 | 354 | 2.23 | 0.92 | 7,777,602 | 8,261,401 |
(1) Cut Off Grade estimated as 250 g/tonne Ag
only; and 228 g/tonne Ag eq net of Pb credit. Estimated Reserves are exclusive
of Resources. 7
(2) Silver equivalent includes Pb credit,
at prices US$12.00/oz -Ag, $0.75/lb -Pb. Pb credit=22 g/tonne
- -Ag.
(3) Mining dilution is included at a minimum mining
width of 2.00m. Estimates do not include mining recovery.
(4) Zinc is not recovered
Total Probable Reserves (3) | ||||||||
Reb 141 | Probable | 2,438 | 1.50 | 1,876 | 19.38 | 2.69 | 147,043 | 148,767 |
Ojuelas Amp | Probable | 4,919 | 1.67 | 598 | 8.87 | 4.09 | 94,651 | 98,131 |
Breccia Keylor | Probable | 3,603 | 3.48 | 516 | 4.92 | 1.32 | 59,790 | 62,339 |
Azul y Oro | Probable | 56,356 | 2.33 | 510 | 1.19 | 0.32 | 924,540 | 964,401 |
Reb 325 (DK Milagros) | Probable | 2,196 | 2.03 | 359 | 7.06 | 0.00 | 25,351 | 26,904 |
Cuerpo 660 E | Probable | 75,632 | 2.00 | 352 | 4.44 | 2.25 | 855,932 | 909,428 |
San Francisco | Probable | 79,582 | 2.31 | 345 | 1.16 | 0.28 | 882,724 | 939,014 |
Dk. San Fco | Probable | 7,758 | 1.93 | 331 | 3.09 | 3.07 | 82,681 | 88,169 |
La Piedra | Probable | 2,740 | 2.48 | 330 | 5.91 | 2.95 | 29,071 | 31,009 |
Bonanza | Probable | 6,899 | 2.40 | 289 | 0.48 | 0.27 | 64,057 | 68,937 |
Breccia Milagros | Probable | 160,916 | Variable > 2.00 | 271 | 0.96 | 0.79 | 1,401,309 | 1,515,128 |
Jorobada | Probable | 10,280 | 2.62 | 261 | 8.46 | 1.92 | 86,367 | 93,638 |
Sn. Javier. Ext | Probable | 82,655 | 1.95 | 223 | 4.67 | 3.95 | 592,976 | 651,439 |
Tailings Dam # 2 (5) | Probable | 4,015,711 | Variable > 2.00 | 168 | 2.43 | 2.67 | 21,690,160 | 21,690,160 |
TOTAL | Probable | 4,511,686 | Over 2.00 | 186 | 2.45 | 2.54 | 26,936,651 | 27,287,462 |
(1) Cut Off Grade estimated as 250 g/tonne Ag
only; and 228 g/tonne Ag eq net of Pb credit. Estimated Reserves are exclusive
of Resources
(2) Silver equivalent includes Pb credit, at
prices US$12.00/oz -Ag, $0.75/lb -Pb. Pb credit=22 g/tonne -Ag.
(3) Mining dilution is included at a minimum mining width of 2.00m.
Estimates do not include mining recovery.
(4) Zinc is not
recovered
(5) Tailings COG estimated at 111 g/tonne.
Total Reserves Proven plus Probable (3) | ||||||||
Total | Proven | 683,992 | Over 2.00 | 354 | 2.23 | 0.92 | 7,777,602 | 8,261,401 |
Total | Probable | 4,511,686 | Over 2.00 | 186 | 2.45 | 2.54 | 26,936,651 | 27,287,462 |
Total Reserves Proven + Probable | 5,195,677 | Over 2.00 | 208 | 2.42 | 2.33 | 34,714,253 | 35,548,863 |
(1) Cut Off Grade estimated as 299 g/tonne Ag only;
and 274 g/tonne Ag eq net of Pb credit. Estimated Reserves are exclusive of
Resources.
(2) Silver equivalent includes Pb credit, at prices US$12.00/oz
-Ag, $0.75/lb -Pb. Pb credit=22 g/tonne -Ag.
(3) Mining dilution is included at a minimum mining width of 2.00m.
Estimates do not include mining recovery.
(4) Zinc is not recovered
Pincock, Allen & Holt | REVISED | 19.12 |
90533 February 26, 2009 |
La Encantada deposits occur in breccia zones and faults or fracturing intersections that make wide and irregular deposits. These generally present widths greater than 2.00m which is estimated to be the minimum mining width due to the mining equipment in use at the mine. Therefore, mining dilution is only significant when the mining is developed along narrow structures. Provisions have been taken to include the mining dilution for those areas.
19.5 Resource Estimation
Resource calculations by FMS at La Encantada are based on projections of the mineralized zones in the underground mine workings; 10m to 15m beyond the areas of reserves for the measured resources; and another 15m beyond the boundaries of the measured resources for the blocks of indicated resources. inferred resources are estimated by projecting up to 50m beyond the indicated resource block boundaries along mineralized structures, and another 15m beyond the blocks width. The estimated resource blocks may be limited by underground levels and previous mining extraction. Longitudinal projections depend on the drift development along the mineralized zones and it may vary from about 50m up to 150m in length.
La Encantada mineral resource estimates were applied only to adjacent blocks from the estimated reserves. Resource estimates were made for blocks that include only oxidized mineralization, such as the Breccia Keylor, Azul y Oro, Breccia Milagros, Cuerpo 660, Cuerpo 660 W and San Francisco deposits. Sulfides mineralization is only estimated in the La Morena deposit. Sulfides are only considered as resources because the processing facilities for the zinc circuit at the plant are not currently operating.
The grade for these blocks is determined from the grade estimated for the adjacent reserve blocks, and sampling in mine workings and drill holes located within the block area.
Geologic potential still exists within the mines area to investigate targets that may result in additional resource development for La Encantada. Exploration and full development of breccia zones, such as: Milagros, San Javier, Keylor, San Francisco and Azul y Oro may result in high-tonnage resource development. The Breccia Milagros appears to be a significant deposit. Other areas that appear to represent important targets for exploration are breccia La Escalera and the area west of the La Prieta deposit beyond the María Isabel fault. This area appears to be downthrown to the west of La Prieta deposit, which represents the largest known deposit within La Encantada area.
In addition to the reserves, La Encantada has estimated resources in blocks within the following areas:
Pincock, Allen & Holt | REVISED | 19.13 |
90533 February 26, 2009 |
Additional inferred resources have been projected in the Azul y Oro, Buenos Aires, Breccia San Javier, Bonanza, Intrusivo Milagros and San Francisco zones.
La Encantadas estimate of measured and indicated resource blocks as reviewed by PAH, is shown in Table 19-6. The measured and indicated silver resources consist of 5.4 million tonnes averaging 176 grams (5.6 oz) per tonne silver, for a total content of 33.4 million ounces of silver equivalent. This resources grade has been estimated in situ, and the silver equivalent content is net of lead credit, at 22 g/tonne Ag. The tailings dams No.1 and No.2 and dumps material have been included as indicated resources. This estimate is based on the following prices: Ag - $12.00/oz and Pb - $0.75 / lb.
Table 19-6 is the measured and indicated resource estimate for La Encantada. PAH notes that these resources are in addition to the previously reported reserves.
La Encantada has estimated additional silver resources at a distance beyond the proven and probable reserves. These additional resources lack sufficient drifting, raising, sampling, drill holes or old workings with production data, and are estimated at a lower degree of confidence than other reserve or resource categories. PAH considers these additional resources to be of an inferred category and they are based on projections of presumed vein continuity ahead, above, and below current mining; and are based on very widely-spaced drill holes, surface sampling or old surface workings. These resources are presented by La Encantada as inferred resources.
Each reserve and resource category presented in this Report are exclusive of each other.
The inferred resources need considerable grade and tonnage information before they can be proved up to Mineable Reserves. To date, La Encantada has demonstrated a continuity along about 4.0 kilometers of strike length and down dip to about 700 meters; so it is reasonable to assume that in the future resources will continue to be converted to ore as additional drifting, crosscutting and raising define vein configurations, sampling and assaying determine the grade, and diamond drilling confirms vein extensions and fills in data gaps. Inferred resources for La Encantada are presented in the lower portion of Table 19-6. Inferred resources are exclusive of reserves and measured and indicated resources.
Pincock, Allen & Holt | REVISED | 19.14 |
90533 February 26, 2009 |
TABLE 19-6
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada
Mine
Mineral Resources Prepared by FMS, Reviewd by PAH as of September
30, 2008 (1)
Total Measured Resources (3) | ||||||||
DEPOSIT | CATEGORY | METRIC TONNES | WIDTH | GRADE | METAL CONTAINED (2) | |||
RESOURCES | meters | Silver, g/tonne | Lead, % | Zinc, % (4) | Silver (Only) oz. | Silver (Eq) oz. | ||
Reb 141 | Measured | 2,438 | 1.50 | 1,876 | 19.38 | 2.69 | 147,043 | 148,767 |
Breccia Keylor | Measured | 10,810 | 3.48 | 516 | 4.92 | 1.32 | 179,367 | 187,013 |
Azul y Oro | Measured | 42,676 | 2.21 | 437 | 1.05 | 0.43 | 599,130 | 629,315 |
Cuerpo 660 W | Measured | 111,337 | 16.71 | 405 | 6.46 | 1.94 | 1,449,725 | 1,528,475 |
Cuerpo 660 | Measured | 191,960 | Variable > 2.00 | 390 | 4.71 | 0.00 | 2,409,828 | 2,545,604 |
Reb 325 (DK Milagros) | Measured | 2,196 | 2.03 | 359 | 7.06 | 0.00 | 25,351 | 26,904 |
Dk. San Fco | Measured | 6,616 | 2.06 | 336 | 3.21 | 3.09 | 71,447 | 76,126 |
San Francisco | Measured | 73,955 | 2.28 | 334 | 0.59 | 0.18 | 794,155 | 846,464 |
Bonanza | Measured | 3,663 | 2.40 | 289 | 0.48 | 0.27 | 34,011 | 36,602 |
TOTAL | Measured | 445,650 | Over 2.00 | 399 | 4.15 | 0.65 | 5,710,055 | 6,025,271 |
(1) Cut Off Grade estimated as 250 g/tonne Ag
only; and 228 g/tonne Ag eq net of Pb credit. Estimated Resources are exclusive
of Reserves.
(2) Silver equivalent includes Pb credit, at
prices US$12.00/oz -Ag, $0.75/lb -Pb. Pb credit=22 g/tonne-Ag.
(3) Mining dilution is included at a minimum mining width of 2.00m.
Estimates do not include mining recovery.
(4) Zinc is not
recovered.
Total Indicated Resources (3) | ||||||||
Azul y oro Ext. al SW | Indicated | 169,231 | 12.00 | 442 | 0.52 | 0.65 | 2,404,879 | 2,524,579 |
Buenos Aires | Indicated | 536,160 | 4.32 | 395 | 0.57 | 0.68 | 6,806,268 | 7,185,503 |
Reb 325 (DK Milagros) | Indicated | 2,196 | 2.03 | 359 | 7.06 | 0.00 | 25,351 | 26,904 |
Dk. San Fco | Indicated | 7,103 | 2.06 | 338 | 3.16 | 3.03 | 77,179 | 82,203 |
San Francisco | Indicated | 73,024 | 2.26 | 332 | 0.44 | 0.18 | 779,462 | 831,113 |
Jorobada | Indicated | 10,280 | 2.62 | 261 | 8.46 | 1.92 | 86,367 | 93,638 |
Sn. Javier. Ext | Indicated | 41,327 | 1.95 | 223 | 4.67 | 3.95 | 296,488 | 325,719 |
Bonanza | Indicated | 27,906 | 2.69 | 204 | 1.05 | 1.05 | 183,029 | 202,767 |
Bonanza | Indicated | 19,855 | 2.46 | 184 | 1.24 | 1.25 | 117,457 | 131,501 |
Bonanza | Indicated | 18,724 | 2.56 | 183 | 0.93 | 0.92 | 110,164 | 123,408 |
Bonanza | Indicated | 33,584 | 2.62 | 181 | 1.28 | 1.29 | 195,435 | 219,189 |
Breccia Milagros | Indicated | 382,673 | 2.12 | 171 | 2.05 | 0.12 | 2,103,851 | 2,374,522 |
OJ Alto del DK la Escon. | Indicated | 839,194 | Variable > 2.00 | 151 | 1.87 | 0.00 | 4,073,427 | 4,667,003 |
Cuerpo 660 (Pilares) | Indicated | 105,445 | Variable > 2.00 | 135 | 1.25 | 7.73 | 457,668 | 532,251 |
Intrusivo Milagros | Indicated | 467,078 | 2.00 | 102 | 0.00 | 0.00 | 1,531,724 | 1,862,096 |
Cuerpo de Zinc N-1535 | Indicated | 151,900 | 1.72 | 93 | 1.21 | 8.85 | 454,184 | 561,625 |
La Morena Sulfides (8) | Indicated | 263,610 | Variable > 2.00 | 65 | 0.76 | 4.14 | 550,892 | 737,347 |
SUB - TOTAL | Indicated | 3,149,290 | Over 2.00 | 200 | 1.18 | 1.30 | 20,253,824 | 22,481,368 |
Jal Producc. 2008 | Indicated | 204,951 | Variable > 2.00 | 111 | 1.84 | 731,595 | 731,595 | |
Talings Dam # 1 | Indicated | 900,374 | Variable > 2.00 | 72 | 0.00 | 0.00 | 2,084,234 | 2,084,234 |
Presa 3 | Indicated | 529,735 | Variable > 2.00 | 68 | 2.73 | 0.06 | 1,154,744 | 1,154,744 |
SUB - TOTAL (5) | Indicated | 1,635,060 | Over 2.00 | 76 | 1.12 | 0.02 | 3,970,572 | 3,970,572 |
Terreros | Indicated | 89,407 | Variable > 2.00 | 131 | 1.29 | 1.53 | 376,561 | 425,427 |
Mine Dumps | Indicated | 57,345 | Variable > 2.00 | 94 | 0.00 | 0.00 | 173,306 | 204,649 |
SUB - TOTAL (6) (7) | Indicated | 146,752 | Over 2.00 | 117 | 0.79 | 0.93 | 549,867 | 630,076 |
TOTAL | Indicated | 4,931,103 | Over 2.00 | 156 | 1.15 | 0.87 | 24,774,263 | 27,082,017 |
(1) Cut Off Grade estimated as 250 g/tonne Ag
only; and 228 g/tonne Ag eq net of Pb credit. Estimated Resources are exclusive
of Reserves. 24,774,263
(2) Silver equivalent includes Pb
credit, at prices US$12.00/oz -Ag, $0.75/lb -Pb. Pb credit=22
g/tonne-Ag.
(3) Mining dilution is included at a minimum
mining width of 2.00m. Estimates do not include mining recovery.
(4) Zinc is not recovered.
(5) Tailings are
considered as indicated resources because require of bulk testing. Cut Off Grade
at Ag-111 g/tonne.
(6) Dump stockpile is considered as
indicated resource because the average grade is below COG.It represents 40.19%
of measured tonnes.
(7) Dump stockpile Cut Off Grade is
estimated at 203 g/tonne Ag, including Pb credit is 186g/tonne Ag. Pb credit =
17 g/tonne Ag.
(8) La Morena sulfides deposit requires of
additional metallurgical testwork to prove its economic recovery. La Encantada
mill does not have an operating zinc circuit at this time.
Total Resources Measured plus Indicated (3) | ||||||||
TOTAL | Measured | 445,650 | Over 2.00 | 399 | 4.15 | 0.65 | 5,710,055 | 6,025,271 |
TOTAL | Indicated | 4,931,103 | Over 2.00 | 156 | 1.15 | 0.87 | 24,774,263 | 27,082,017 |
Total Resources Measured + Indicated | 5,376,753 | Over 2.00 | 176 | 1.40 | 0.85 | 30,484,318 | 33,107,288 |
(1) Cut Off Grade estimated as 250 g/tonne Ag
only; and 228 g/tonne Ag eq net of Pb credit. Estimated Resources are exclusive
of Reserves.
(2) Silver equivalent includes Pb credit, at
prices US$12.00/oz -Ag, $0.75/lb -Pb. Pb credit=22 g/tonne-Ag.
(3) Mining dilution is included at a minimum mining width of 2.00m.
Estimates do not include mining recovery.
(4) Zinc is not
recovered.
(5) Tailings are considered as indicated
resources because require of bulk testing. Cut Off Grade at Ag-111
g/tonne.
(6) Dump stockpile is considered as indicated
resource because the average grade is below COG.It represents 40.19% of measured
tonnes.
(7) Dump stockpile Cut Off Grade is estimated at
203 g/tonne Ag, including Pb credit is 186g/tonne Ag. Pb credit = 17 g/tonne
Ag.
(8) La Morena sulfides deposit requires of additional
metallurgical testwork to prove its economic recovery. La Encantada mill does
not have an operating zinc circuit at this time.
Total Inferred Resources (1) (2) (3) | ||||||||
Azul y Oro ext. al SW | Inferred | 194,163 | 10.85 | 454 | 0.49 | 0.66 | 2,834,088 | 2,971,423 |
Azul y Oro | Inferred | 97,164 | 2.27 | 434 | 0.93 | 0.38 | 1,355,415 | 1,424,141 |
Dk. San Fco | Inferred | 27,065 | 2.06 | 390 | 8.28 | 2.43 | 339,646 | 358,789 |
Reb 325 | Inferred | 2,196 | 2.03 | 359 | 7.06 | 0.00 | 25,351 | 26,904 |
Buenos Aires | Inferred | 561,824 | 3.40 | 339 | 0.50 | 0.59 | 6,122,437 | 6,519,825 |
San Francisco | Inferred | 186,000 | 2.40 | 304 | 0.64 | 0.14 | 1,817,932 | 1,949,492 |
Sn. Javier. Ext | Inferred | 171,509 | 1.95 | 223 | 4.67 | 3.95 | 1,230,425 | 1,351,736 |
Bonanza | Inferred | 22,000 | 2.77 | 220 | 1.12 | 1.12 | 155,610 | 171,171 |
Breccia San Javier | Inferred | 1,015,000 | Variable > 2.00 | 105 | 0.57 | 0.78 | 3,426,465 | 4,144,392 |
Intrusivo Milagros | Inferred | 280,000 | 2.00 | 102 | 0.00 | 0.00 | 918,225 | 1,116,274 |
TOTAL (4) | Inferred | 2,556,921 | Variable > 2.00 | 222 | 0.87 | 0.82 | 18,225,593 | 20,034,145 |
(1) Cut Off Grade estimated as 250 g/tonne Ag only;
and 228 g/tonne Ag eq net of Pb credit. Estimated Resources are exclusive of
Reserves.
(2) Silver equivalent includes Pb credit, at prices US$12.00/oz
-Ag, $0.75/lb -Pb. Pb credit=22 g/tonne-Ag.
(3) Mining dilution is included at over 2.00m width. Estimates do not include
mining recovery.
(4) Zinc is not recovered.
Pincock, Allen & Holt | REVISED | 19.15 |
90533 February 26, 2009 |
19.6 Conclusion
PAH believes that these reserve and resource estimates have been reasonably prepared and conform to acceptable engineering standards for reporting of resources. PAH believes that the classification of the reserves and resources meets the standards of Canadian National Instrument NI 43-101 and the definitions of the Canadian Institute of Mining, Metallurgy and Petroleum (CIM).
The reserves and resources herein reported by La Encantada Silver Mine were reviewed by PAH and constitute part of an operation by Minera La Encantada, a Mexican subsidiary of FMS. There are no significant technical, legal, environmental, political or other kind of restrictions; therefore, in PAHs opinion these reserves and resources may not be materially affected by issues that could prevent their extraction and processing.
Pincock, Allen & Holt | REVISED | 19.16 |
90533 February 26, 2009 |
20.0 OTHER RELEVANT DATA AND INFORMATION
La Encantada mine has been in operation for over 25 years. Reported silver production for that period by Peñoles is about 80 million ounces of silver, in addition to significant lead content and minor gold. This production was extracted from about 6 Million tonnes of ore.
Historical mineral concentrations at La Encantada consist of mineralized breccia pipes (chimneys) and metasomatic zones, which typically contain up to 2.0 million tonnes; breccia zones that range up to 1.0 million tonnes; vein deposits that may contain up to 0.5 million tonnes, and mantos or bedded deposits that may hold up to 50,000 tonnes of usually high grade concentrations.
Major underground workings were developed by Peñoles at La Encantada, to connect the various parts of the mine, as well as to explore and mine mineralized zones within the Aurora limestone/dolomite formation. These workings extend along a 4km-long mineralized structural zone, with access to mine levels at elevations of 1,535m to about 2,300m. These connections are accessible by shafts and ramps.
Through the underground development, numerous exploration targets have been projected, identified or discovered.
At the closure of La Encantada mine by Peñoles in June 2002, several exploration targets remained to be investigated. Some of these areas require significant development as well as drilling from underground locations, such as Breccia Milagros, Breccia San Javier, Bonanza zone, Mantos San Francisco, etc. Other longer-term exploration targets may result in discoveries which may be as significant as those previously mined such as La Prieta and La Escondida, these areas are La Escalera, Ojuela and Cuerpo 660.
Other important areas for future development by FMS are represented by primary sulfide mineralization located at depth, in proximity to the granodiorite intrusive stocks, such as Cuerpo La Morena, Cuerpos 660 E and W, and Ojuela, which may enhance and extend La Encantada mine life.
La Encantada exploration investigations have resulted in validation and a significant increment of previous reserve and resource estimates. Proven and probable reserve estimates as of September 30, 2007 are about 70 percent higher than the reserves estimated for May 31, 2007, while measured and indicated resources were augmented nearly 500 percent, including tailings from previous Peñoles operations, which have been tested for processing by cyanidation. Inferred resources are also increased by about 30 percent. Numerous additional exploration targets have been identified by La Encantada staff.
During the exploration program for 2008, La Encantada exploration team discovered additional resources while drilling another target. The new area has been denominated Buenos Aires and partially investigated with about 15 drill holes resulting in indicated and inferred resources containing about 536,000 tonnes of Indicated Resources at an average grade of 395 g/tonne Ag (7.2 million ounces of silver equivalent) and 560,000 tonnes of Inferred Resources at an average grade of 339 g/tonne Ag (6.5 million ounces of silver equivalent). Silver equivalent includes Pb credits. Additional drilling and underground development are in progress to further define the mineral deposit and upgrade the resources.
Pincock, Allen & Holt | REVISED | 20.1 |
90533 February 26, 2009 |
In PAHs opinion, La Encantada has developed a highly successful exploration program based on underground development and drilling which has resulted in increasing resources and reserves and identifying other exploration targets; therefore, La Encantada investments in exploration and development have been well justified.
Pincock, Allen & Holt | REVISED | 20.2 |
90533 February 26, 2009 |
21.0 INTERPRETATION AND CONCLUSIONS
Recorded production in about 25 years by Minera La Encantada, S.A. de C.V. is approximately 6.0 million tonnes of ore at an average grade of Ag-418 g/t (13.44 oz/t) and Pb-9.83 percent (over 80 million ounces of silver and about 1.3 billion lbs of lead) until June 2002 when Peñoles shut the operation down. Mining and processing by FMS through its wholly-owned subsidiaries, Desmín and Minera La Encantada, was approximately 175,000 tonnes of ore to October 31, 2007.
Mineralization at La Encantada is a typical assemblage of metasomatic deposits with a high content of silver and lead. This mineral assemblage has been affected by a long process of oxidation and secondary enrichment. The most important mineralization consists of unconsolidated massive concentrations of oxides including hematite, limonite and other iron oxides as well as carbonates and sulphates, including the minor presence of zinc oxides. Silver and lead represent the main economic minerals within the oxidized deposits at La Encantada. Silver mineralization occurs as argentite and native silver. Lead mineralization is present as carbonates (cerussite) and sulfates (anglesite) and other oxides.
La Encantada mineral assemblage occurs within a range of about 435m in vertical extension (2035m to 1600m asl). Below the 1600m elevation, at the La Morena deposit in the SW portion of La Encantada area, primary sulfide mineralization has been identified. This mineralization includes primarily sphalerite, galena and pyrite. FMS has identified other regional areas of geologic interest. These areas appear to represent potential exploration targets that may extend the mineralized system.
FMS initiated preliminary drilling, during the period of June through October, 2007 while expecting new drill rigs to carry out a more comprehensive drilling program to investigate several targets. Exploration investigations during this period by La Encantada staff have resulted in about 6.2 million tonnes of additional reserve and resource blocks within the mining areas. These include dumps materials and tailings being investigated by FMS as resources. A new mineralized zone located within the Azul y Oro and La Escalera breccia zones was recently discovered by diamond drilling. Currently it is estimated to contain about 850,000 tonnes of silver mineralization containing about 13 million ounces of silver equivalent. This area requires of additional drilling for upgrading the currently delineated resources.
The mine was initially developed from the shafts as a conventional operation with rail haulage levels, and utilizing standard rail-bound loading and hauling equipment. Subsequently, La Encantada mine has been converted to a mainly trackless operation, although rail haulage is still used on a few of the deeper levels of the mine.
The main access to the current mine operations is a trackless adit at the 1,870 elevation. This working has been enlarged to accommodate 20-t capacity highway-type dump trucks for ore and waste haulage from the mine. Drifts and ramps are driven with cross-sectional area of about 3- X 3- meters, and the enlarged drifts and ramps to accommodate the larger dump trucks are about 4.5 - X 5.0 - meters in cross-section. Most areas of the mine are unsupported, but in a few places, rock bolts and wire mesh has been installed, and in other heavy ground areas, it has been necessary to install steel arches with timber lagging.
Pincock, Allen & Holt | REVISED | 21.1 |
90533 February 26, 2009 |
A ramp system in the interior of the mine provides access for low-profile diesel mobile equipment up to the 2035 level and down to the 1710 level. The portion of the ramp above the 1870 level is being enlarged to accommodate the highway-type dump trucks. Mining operations at La Encantada mine are partially mechanized. Drilling of headings for both development and stoping is accomplished using pneumatic hand-held jackleg machines. Loading and tramming is done with diesel-powered, low profile front-end loaders (load-haul-dumps, or LHDs), and haulage is usually with highway-type diesel rear-dump trucks, or battery powered rail haulage trains.
The ore processed at La Encantada is a complex mixture of oxide and sulfide minerals and is consequently difficult to process efficiently. The principal economic minerals are as follows:
The ore is relatively soft and friable, which is easily crushed and milled. The ore processing method consists of crushing and grinding followed by two sequential flotation steps. The first consists of sulfide mineral flotation and the second is oxide mineral flotation. Installed capacity at La Encantada is 800 tpd; however, it is currently operated at about 800 tpd. Recoveries are modest, a reflection of the difficult mineralogy of the rock; operating costs are modest, a consequence of the softness of the rock.
FMS are currently building a 3,500 tpd cyanide leach plant and plans are to switch from flotation processing to cyanidation of the mined ore and to process it in conjunction with reclaimed tailings that have accumulated on the site over the prior decades of operation. There is some uncertainty as to the outcome of this plan since it is based on limited testwork. The plant will go into operation in the second quarter of 2009 and actual results established by yearend.
Peñoles estimated proven and probable reserves as of December 2002 amounted to 484,857 tonnes at an average grade of 570 g/t Ag and 3.98 percent Pb. No cutoff grade was reported. The estimated reserves were included in the deposits of: Bonanza, El Milagro, Estructuras Irregulares Bonanza, Estructuras Irregulares San Javier, Breccia San Javier, Ojuelas, San Francisco, and Azul y Oro deposits.
FMS has initiated exploration programs based on drifting, channel sampling, drilling, geophysical investigations and some geochemical studies. Peñoles reported (2002) reserve or resource blocks are a primary target for confirmation, validation and further exploration by FMS, as well as other promising areas of reserves.
PAH has reviewed La Encantada Reserve update of October 31, 2007, along with factors for mining dilution and recovery. In addition, the sampling methods, assaying procedures, compositing methods, data handling, cutoff grade application and grade calculations were reviewed. Several reserve blocks were cross-checked to track data handling from the initial assays to the final tonnage and grade calculation to ensure that the stated methods and practices were observed.
Pincock, Allen & Holt | REVISED | 21.2 |
90533 February 26, 2009 |
La Encantada has estimated mineable reserves for the following deposits:
The total in-situ diluted Reserve as of September 30, 2008, at a minimum mining width of 2.00m, as reviewed by PAH, is 5.2 million tonnes including 4.0 million tones of tailings, averaging 208 grams (6.7 oz) per tonne silver and 2.42 percent (53 lb/tonne) lead, for a total of 35.5 million contained ounces of silver net of lead credit. The tailings appear to be amenable for reprocessing by cyanidation; therefore, they have been included as probable reserves.
In addition to reserves, the La Encantada holds measured and indicated mineral resources that include estimates for the following areas: Azul y Oro, Buenos Aires, Breccia Milagros, Cuerpo 660, Cuerpo 660 W and Breccia Keylor deposits. Sulfide mineralization is only estimated in the La Morena deposit. Sulfides are only considered as Resources because the processing facilities for the zinc circuit at the plant are currently out of order. Dump materials have been screened, concentrated, and processed in the flotation plant to fill operating capacity, and have been included as resources after screening. Estimated resources for La Encantada Silver Mine total 5.4 million tonnes at an average grade of 176 g/tonne (5.7 oz/tonne) Ag and 1.40 percent (31 lb/tonne) Pb. Measured and indicated resources to September 30, 2008, are estimated to contain about 33.1 million ounces of silver equivalent net of lead credit.
In addition to measured and indicated resources, La Encantada has estimated about 2.6 million tonnes of inferred resources at an average grade of 220 g/tonne (7 oz/tonne) Ag and 1.0 percent (22 lb/tonne) Pb, for a total silver equivalent of 20.0 million ounces.
To date, La Encantada has demonstrated a continuity along approximately 4.0 kilometers of strike length and down dip for about 700 meters; so it is reasonable to assume that in the future resources will continue to be converted to ore as additional drifting, crosscutting and raising define vein configurations, sampling and assaying determine the grade, and diamond drilling confirms vein extensions and fills in data gaps. Geophysical investigations carried out during the period have confirmed previously delineated anomalous zones which require of a drilling program from surface sites.
Pincock, Allen & Holt | REVISED | 21.3 |
90533 February 26, 2009 |
During the period of January to September 2008 the La Encantada mine operation totaled 178,480 tonnes of silver mineralization which was extracted from previously estimated reserves (70,000 tonnes) and from other areas (108,480 tonnes) that were discovered during the development for extraction of the reserves.
All reserve and resource blocks at La Encantada are exclusive of each category.
PAH believes that these reserve and resource estimates have been reasonably prepared and conform to acceptable engineering standards for reporting of reserves and resources. PAH believes that La Encantada Silver Mine classification of reserves and resources meets the standards of Canadian National Instrument NI 43-101 and the definitions of the Canadian Institute of Mining, Metallurgy and Petroleum (CIM).
An economic analysis of FMSs La Encantada Silver Mine indicates that the mines reserve/resources may be extracted at a profit, and PAH did not identify any significant technical, legal, environmental, political or other kind of restrictions; therefore, in PAHs opinion these reserves and resources may not be materially affected by issues that could prevent their extraction and processing.
Pincock, Allen & Holt | REVISED | 21.4 |
90533 February 26, 2009 |
22.0 RECOMMENDATIONS
La Encantada Silver Mine has been in operation since the 1950s, with intense extraction and processing operations from the early 1970s. Its production, by Peñoles records, amounts to over 80 million ounces of silver and over 1.3 billion pounds of lead. La Encantada is by no means exhausted; its geologic potential remains to be fully explored. Several zones within the mine area have been identified that may contain significant mineralization, such as Breccia La Escalera, Breccia Milagros, Breccia San Javier and others that enable the operators to increase La Encantadas production. Aside from the oxidized mineralization, there are sulfide deposits identified within the skarn areas at Cuerpo 660, La Morena and deeper areas under the La Prieta and La Escondida chimneys. These areas require intense exploration direct methods, such as diamond drilling and drifting.
FMS has initiated an aggressive program of exploration based on drifting and diamond drilling. Preliminary results of this program have resulted in a significant increment of resources and reserves for the La Encantada Silver Mine for the period between June and October, 2007. For instance, the Breccia Milagros and the San Francisco areas have produced high grade ores through exploration development and appear to be developing into significant ore deposits. Exploration drilling for the Azul y Oro zone has intersected other mineralized zone located between the Azul y Oro and the La Escalera breccia zones denominated as Buenos Aires. This zone consists of a series of mineralized structures containing high grade silver mineralization which full extension is being investigated.
PAH agrees with the continued implementation of the exploration program and recommends additional support for exploration activities at La Encantada. Positive results would develop resources into reserves and extend the mines life.
Care must be taken to prioritize the exploration targets since the area holds a broad potential for development and possible discovery of new ore bodies. Potential high volume areas should have priority in the exploration program, since these large volume deposits could potentially help to lower mine operating costs.
FMS has suggested an exploration budget of US$2.50 Million for 2009 at La Encantada. If successful, this program may result in a significant increment of resources and additional reserves. The program includes approximately 7,850 meters of drilling from underground sites and 5,000 meters from surface locations. Underground exploration development in drifting, access ramps, crosscutting and drill sites preparation amounts to about 850 meters for the year. The budget for this program also includes geochemical sampling of about 500 samples to validate geophysical exploration targets. PAH believes that this exploration program, budget and exploration targets are reasonable for continued investigation the La Encantada geologic potential. Table 22-1 shows the La Encantada exploration budget for 2009.
PAH recommends that La Encantada follow budgeted capital-expenditure plans for the ore processing facilities. With the exception of the funds budgeted to complete the cyanidation plant, the plan is generic with a fixed annual amount for ongoing capital expenditures. The estimated 2009 cost for completing the cyanidation plant is $8.2 million of the 21.5 million original budget and the ongoing annual ore-processing-related capital expenditure estimate is $135,000.
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90533 February 26, 2009 |
TABLE 22-1
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
PAH Recommendations Estimated Budget
Exploration Activities | Objective | Area | Total Develop, m | Est. Cost US$ |
Underground Drilling | Explore extensions, confirm and delineate Resource blocks. | Azul y Oro, Buenos Aires, La Escalera, Cedrito, Bonanza, Falla María Isabel. | 25 DH - 7,850 | 750,000 |
Underground Development | Crosscuts, drifts, ramps and drill sites. | 1790 Mine Level, Buenos Aires zone, San Francisco, Bonanza and Azul y Oro. | 850 | 340,000 |
Surface Drilling | Geophysical anomalies | El Plomo, Anomalies "A", "B", "C", "D". |
5,000 | 750,000 |
Geochemical Surveying | Evaluate Geophysical Anomalies | El Plomo, La Escalera, etc. | 500 | 25,000 |
Geotechnical Studies | Investigate La Prieta and Escondida area. | San Francisco and María Isabel Shafts | - | 250,000 |
UG Mine Ventilation System | Study on ventilation system | Entire Mine | - | 250,000 |
Other | Improve Ore Processing | Flotation and Cyanide Plants | - | 135,000 |
TOTAL | 2,500,000 |
Much of the mines mobile equipment at La Encantada is very old and requires replacement. FMS has a plan in place to replace some of the older mine equipment in the near future and has purchased some new units in 2008 and plans additional purchases in 2009.
PAH has noted the possibility of significant ground movements that may affect the integrity of either or both the San Francisco and Maria Isabel Shafts, which are the major ore hoisting and service facilities for the mine. In addition, the geotechnical studies should also include ground control methods at the mine and recommendations for improvement. The estimated cost of the initial geotechnical study will range from $150,000 to $250,000.
PAH also notes that the ventilation system in the mine is inadequate and much improvement is needed. A comprehensive survey and study of the ventilation system and corresponding recommendations by an outside expert is recommended. The estimated cost of the initial survey will be in the range of $100,000 to $250,000.
The Capital expenditures suggested for the plant and mine are scheduled to improve the operation and, through a successful exploration program, increase the mines reserves and resources and therefore the mine life. A summary of the PAH recommendation is found in Table 22-1.
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90533 February 26, 2009 |
23.0 REFERENCES
Resource and Reserve Estimates by First Majestic Silver Corp. for La Encantada Silver Mine. Prepared by FMS staff and reviewed by PAH. September 30, 2008. | ||
Exploration data including drilling, core sampling, underground development, mapping, channel sampling, and operating results carried out and provided to PAH by La Encantada Staff. September 30, 2008. | ||
Monthly Operating Reports of La Encantada Silver Mine, including exploration, mine, processing plant all supporting operating aspects of the mine operation for the months of January through September 30, 2008. Prepared by La Encantada General Manager and Staff. | ||
Technical Report for the La Encantada Silver Mine, Coahuila State, México, prepared for First Majestic Silver Corp. dated July 24, 2007, Amended by Pincock, Allen & Holt, Inc., and was published in SEDAR on July 25, 2007, is referred to as Technical Report Amended herein. | ||
Pruebas Metalúrgicas para Determinar la Disolucion de Plata y Oro for Cianuracion, de Cinco Muestras de Mineral. Preparado para Minera La Encantada, S.A. de C.V., por SGS de Mexico, S.A. de C.V. Durango, Durango, 22 de Junio de 2007. | ||
Pruebas Metalúrgicas para Determinar la Disolución de Plata y Oro por Cianuaración, de dos Muestras de Mineral. Preparada para Minera La Encantada, S.A. de C.V., por SGS de México, S.A. de C.V. Durango, Durango, 12 de Julio de 2007. | ||
Pruebas Metalúrgicas para Determinar Las Extracciones de Plata y Oro por Cianuración y Concentración Gravimétrica de Dos Muestras de Jales de La Encantada, Además del ¥ndice de Bond de Una de Ellas. Preparada para First Majestic, S.A. de C.V., por SGS de México, S.A. de C.V., Durango, Durango, Marzo 14, 2008. | ||
Peñoles (Largest Silver producer in the World) information as owner and operator of La Encantada Mine for a period of 25 years, including public records, operating reports, geological studies, surveying, sampling data, drilling, geologic modeling and resource estimates, production records and historical reserve estimates as of January 2003. It includes the following reports: | ||
Plan y Programa de Exploración 2001 2002. Prepared by Ing. Pantaleón Trejo, Manager of Explorations for Mining Operations, Peñoles. June 2002. | ||
Desglose de Mineral Probado y Probable por Cuerpos para 2003. Prepared by: Minera La Encantada, S.A. de C.V., Ing. Pantaleón Trejo, Manager of Explorations for Mining Operations, Peñoles. |
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90533 February 26, 2009 |
Relación de Fundos Mineros Minera La Encantada, S.A. de C.V., Unidad David Contreras. Prepared by Minera La Encantada, Peñoles. Febrero 2007. This report was updated by FMS including additional claims in May 2007. | ||
Database and modeling files for the La Encantada deposits by Peñoles. Provided to FMS in April 2007. | ||
Legal Opinions Minera La Encantada, S.A. de C.V., a wholly owned subsidiary of First Majestic Silver Corp. Legal Opinions by Durango-based office of legal advisers, by Mr. Carlos Galván Pastoriza, Abogado, prepared on October 31, 2008. | ||
Environmental and Permitting Opinions Minera La Encantada, S.A. de C.V., a wholly owned subsidiary of First Majestic Silver Corp. Opinion and List of Permits by Corporate Environmental and Permitting Adviser, by Mr. José Luis Hernández Santibañez, prepared on October 31, 2008. | ||
Geochemical and Isotopic Study of Calcite Stockworks at La Encantada Mining District; Relationships with Orebodies and Implications for Exploration. A Thesis submitted to the Faculty of the DEPARTMENT OF MINING AND GEOLOGICAL ENGINEERING, in partial fulfillment of the requirements for the degree of Master of Science with a Major in Geological Engineering. By: Raúl Díaz-Unzueta, 1987. | ||
Evaluación Geológica Unidad Minera La Encantada, Municipio de Ocampo, Coahuila, México. Prepared by: Exploraciones Geológico-Mineras de Occidente, S.A. de C.V. Septiembre 2006. | ||
Geologic Evaluation of the La Encantada Property, State of Coahuila de Zaragoza, México. Prepared by: J.N. Helsen, Ph.D., P. Geo. December 2006. | ||
Data provided by Desmín, S.A. de C.V. as operator of La Encantada under lease from Peñoles, July 1, 2004 to November 1, 2006. | ||
Information provided by FMS as owner and operator of La Encantada mine. | ||
PAH observations on site visit during the periods of May 18 23 and November 13 18, 2007 and October 28 31, 2008. |
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90533 February 26, 2009 |
24.0 DATE AND SIGNATURE PAGE
Leonel López, C.P.G.
165 S. Union Blvd. Suite
950
Lakewood, Colorado 80228
Phone (303)986-6950
Fax (303)987-8907
leonel.lopez@pincock.com
I, Leonel López, C.P.G., am a professional geologist and Principal Geologist for Pincock, Allen & Holt, Inc. of 165 S. Union Boulevard, Suite 950, Lakewood, Colorado, USA. This certificate applies to the Technical Report for the La Encantada Silver Mine, Coahuila State, Mexico dated February 26, 2009 (the Technical Report).
1. |
I am a Professional Geologist (PG-2407) in the state of Wyoming, USA, a Certified Professional Geologist (CPG-08359) in the American Institute of Professional Geologists, a Member (No. 1943910RM) as SME Founding Registered Member, a registered Geological Engineer (Cédula Profesional #1191), in the Universidad Nacional Autónoma de México, a member of the International Association on the Genesis of Ore Deposits, a member of the Society of Economic Geologists, and a member of the Association of Exploration Geochemists. |
2. |
I graduated from the Universidad Nacional Autónoma de México with the title of Ingeniero Geólogo in 1966 and subsequently have taken numerous short courses in Economic Evaluation and Investment Decision Methods at Colorado School of Mines, other short courses and seminars on mineral economics and other technical and economic subjects in related professional seminars. I have practiced my profession continuously since 1963. |
3. |
Since 1963, I have been involved in mineral exploration and economic evaluation of mineral properties for gold, silver, lead, zinc, copper, antimony, and non-metallic deposits as fluorite, barite, dolomite and coal deposits in Canada, United States of America, México, Guatemala, Costa Rica, Nicaragua, Ecuador, Venezuela, Perú, Bolivia, Chile, Brazil and Argentina. |
4. |
As a result of my experience and qualification I am a Qualified Person as defined in NI 43-101. |
5. |
I am presently a Principal Geologist with the international resource and mining consulting company of Pincock, Allen & Holt, Inc. and have been employed since December 2003, and was formerly employed by the same firm from 1988 to 1993. |
6. |
I have previously worked on the La Encantada Deposit North, as Division Manager of Exploration for Peñoles until 1985. As part of this study, I visited the project site from May 1523, November 11-18, 2007 and October 2931, 2008 for the purposes of observing site layout and infrastructure, examining the deposit geology, inspecting the underground mine, reviewing sampling procedures, reviewing available exploration and reserve and resource estimates and data, and discussing the project with site personnel. |
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7. |
I am the primary author of the Technical Report. I am responsible for and supervised the preparation of all the report sections. I have visited the project in May 2007, and November, 2007 and in July and October-November, 2008, and I have acted as Project Manager for the preparation of this Technical Report. |
8. |
As of the date of this certificate, to the best of my knowledge, information and belief, the Technical Report contains all scientific and technical information that is required to be disclosed to make the Technical Report not misleading. |
9. |
I am independent of First Majestic Silver Corp. in accordance with the application of Section 1.4 of National Instrument 43-101. |
10. |
I have read National Instrument 43-101, Form 43-101F1 and this report has been prepared in compliance with NI 43-101 and Form 43-101F1. |
11. |
I consent to the filing of the Technical Report with any stock exchange and other regulatory authority and any publication by them, including electronic publications in the public company files, on their websites accessible by the public. |
Dated in Lakewood, Colorado, this 26th day of February 2009
Leonel López
______________________________
Leonel López, C.P.G.
Pincock, Allen & Holt | REVISED | 24.2 |
90533 February 26, 2009 |
Richard Addison
165 So. Union Blvd., Suite
950
Lakewood, CO 80228
Phone (303) 986-6950
Fax (303) 987-8907
dick.addison@pincock.com
I, Richard Addison, P.E., C. Eng., Eur. Ing., for Pincock, Allen & Holt, Inc. of 165 S. Union Boulevard, Suite 950, Lakewood, Colorado, USA. This certificate applies to the Technical Report for the La Encantada Silver Mine, Coahuila State, Mexico dated February 26, 2009 (the Technical Report).
1. |
My residential address is: 857 S. Van Gordon Court, #G207, Lakewood, Colorado 80228. |
2. |
I graduated from the Camborne School of Mines in England as an Honors Associate in 1964 and subsequently obtained a Master of Science degree in metallurgical engineering from the Colorado School of Mines in 1968. I have practiced my profession continuously since 1964. |
3. |
I am a Registered Professional Engineer (#3198) in the state of Nevada, USA, a Chartered Engineer in the U.K., and a registered European Engineer in the EU. I am a member of the American Institute of Mining, Metallurgical, and Petroleum Engineers and a member of The Institute of Materials, Minerals and Mining in the U.K. |
4. |
I have worked as a metallurgical engineer for a total of 44 years since my graduation from university and have been involved in the evaluation and operation of mineral properties for gold, silver, copper, lead, zinc, tin, aluminum, iron, potash, gypsum, limestone, barite, clay, sulfur, pyrite, oil shale, coal, and diamonds in the United States, Canada, Mexico, Dominican Republic, Honduras, Nicaragua, Costa Rica, Panama, Venezuela, Guyana, Peru, Ecuador, Bolivia, Argentina, Chile, Spain, Portugal, Britain, Bulgaria, Indonesia, Papua New Guinea, the Philippines, Japan, Tunisia, Ghana, Zambia, South Africa, Russia, Kyrghyzstan, Brazil, and Australia. |
5. |
I have read the definition of qualified person set out in National Instrument 43-101 (NI 43- 101) and certify that by reason of my education, affiliation with a professional association (as defined in NI 43-101) and past relevant work experience, I fulfill the requirements to be a qualified person for the purposes of NI 43-101. |
6. |
I am responsible for the preparation of the paragraph summarizing ore processing in Section 3.0, Executive Summary; Section 18 Metallurgical Testing and Mineral Processing; those paragraphs covering ore processing in Section 21, Interpretations and Conclusions; Section 25.4, Mineral Processing Plant; and Section 25.7, Product Marketing. |
7. |
As of the date of the certificate, to the best of my knowledge, information and belief, the technical report contains all scientific and technical information that is required to disclose to make the technical report not misleading. |
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90533 February 26, 2009 |
8. |
I am independent of the Issuer in accordance with Section 1.4 of NI 43-101. |
9. |
I have read NI 43-101 and Form 43-101F1, and the Technical Report has been prepared in compliance with that instrument and form. |
10. |
I consent to the filing of the Technical Report with any securities regulatory authority, stock exchange or other regulatory authority and any publication by them, including electronic publication in the public company files on their websites accessible by the public, of the Technical Report. |
Dated in Lakewood, Colorado, this 26th day of February 2009
Richard Addison
_______________________________________
Richard Addison, P.E., C. Eng., Eur. Ing.
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25.0 |
ADDITIONAL REQUIREMENTS FOR TECHNICAL REPORTS ON DEVELOPMENT PROPERTIES AND PRODUCTION PROPERTIES |
25.1 Introduction
La Encantada Silver Mine is located in the municipality of Ocampo in the northwestern part of the state of Coahuila, Mexico. The mining district in which La Encantada is located is the David Contreras (La Encantada) district. Mining has been carried out in La Encantada area since the early 1940s with some limited extraction of high-grade lead-silver oxides from the skarn deposits of the area. Historically ore extraction in the district was done by underground methods, and this has been continued at La Encantada.
In the early 1970s a 60/40 joint venture was formed between Lacana Mining of Canada and Industrias Peñoles to develop and exploit the silver-lead orebodies discovered at La Encantada. The joint venture, operating under the name of Compañia Minera La Encantada, S.A. de C.V., sank two main production shafts for La Encantada project, the San Francisco and the Maria Isabel, and started exploitation of La Prieta high-grade silver chimney. The operator constructed a magnetic separation plant to process the ore at project inception, but two years later, replaced the plant with a 1,000 tonnes per day differential flotation plant. All products from this plant are concentrates, which were, and continue to be, marketed to the Peñoles Met-Mex smelter, located in the city of Torreón, Coahuila. Peñoles, as the operator, worked the mine steadily from 1974 until 1986, when it was stopped due to poor profitability. Peñoles restarted operations in 1990 after discovery of significant high-grade reserves.
During the 35 years Peñoles operated the property, about 6.0 million tonnes of mainly oxidized silver-lead ores, which averaged about 418 grams Ag and 9.9 percent Pb per tonne, were mined and processed. In 2003, Peñoles leased the mine to a small company, Desmín, S.A. de C.V., who operated it from 2003 until November 2006, when Desmín was acquired by First Majestic Silver Corporation (FMS) giving FMS control over the mine. FMS then acquired Minera La Encantada S.A. de C.V. (a wholly owned subsidiary of Peñoles) in March 2007 giving FMS complete ownership of the mine. There was no hiatus in the mine production program through the acquisition period, and Desmín continued the operations until First Majestic took over in late November 2006. First Majestic continued with Desmíns development and production programs after the acquisition. FMS made several changes in early 2007, and current production is about 20,000 tonnes per month of oxidized silver-lead ores. Mill feed is not only derived from the underground mine, but also from old dump material left by both Peñoles and Desmín; the split for the first nine months of FMS operations in 2008 is about 15,000 tonnes per month from the mine and 6,000 tonnes per month from dump material. Ore is campaign-milled at the site in the differential flotation plant, which was originally constructed by Peñoles in the 1970s. The mine produces a silver-lead concentrate, and paid metal production is currently in average for the period of January to September about 112,800 ounces of silver and 235,300 pounds of lead per month.
The historic production from La Encantada has resulted in storage of about 5.0 million tonnes of mainly flotation tailings, which still contain significant silver values. The company is currently constructing a 3,500-tpd process plant in which the tailings will be reprocessed together with mine and dump ore, and silver and small amounts of gold will be recovered in a cyanide circuit with a Merrill-Crowe precious metals recovery system. FMS projects that 3.6 million ounces of silver will be produced per annum, of which 1.8 million ounces will be obtained from the old tailings and 1.8 million ounces will be obtained from processing mine ore and dump recovery ore. The new plant is scheduled for startup in the second quarter of 2009.
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25.2 Mine Design and Production
La Encantada mine has largely been developed below ore zones indicated from surface exploration work within a block about four kilometers long, 700 meters wide and 500 meters in height. The mine was initially developed from shafts as a conventional operation with rail haulage levels, and utilizing standard rail-bound loading and hauling equipment. Subsequently, La Encantada was converted to a mainly trackless operation, although rail haulage is still used on a few levels of the mine. The mine has been developed to the northeast of the shafts over a vertical range of about 400 meters from the surface (2,035 meters asl) to about the 1525 level (1,525 meters asl), where the water table has been encountered. The mine has not been developed into the large prospective area to the southwest of the shafts, which is situated at the southwest boundary of the developed mine area.
The San Francisco and María Isabel shafts were sunk by the Peñoles-Lacana joint venture, mainly for the development and extraction of the Escondida and La Prieta chimneys and these shafts continue to be used by the current operators. The collar elevations of both shafts, which are situated only about 100 meters apart, is 1,800 meters asl for the María Isabel, and 1805 meters asl for the San Francisco, and the depths of both are about 300 meters. Both the San Francisco and María Isabel Shafts provide access to the deeper levels of La Prieta and Escondida areas of the mine.
The southern-most María Isabel Shaft is L-shaped with a manway cut-out and it is equipped with two in-balance 3.7 -t capacity skips, and a man cage. The man cage capacity is about 15 people. The furnishings in the shaft are all constructed of steel, including dividers. The guides for the ore skips are cables, and the guides for the man cage are steel H-beams. The main air lines and electric power cables into the mine are installed in the manway compartment of the María Isabel Shaft. The María Isabel ore hoist is a 500-hp Canadian Ingersoll-Rand 2-drum hoist, and the man-hoist is a Vulcan 125-hp 1-drum hoist.
The rectangular San Francisco Shaft is set up for ore hoisting only, with only a small emergency manway located in a corner of the shaft. The Shaft is fitted with two in-balance 4.8 -t capacity skips, but has no man cage. The main pumping station for the mine is located on the San Francisco Shaft, and the mine pump lines are located in the shaft near the emergency manway. The San Francisco ore hoist is a 2-drum 400-hp Canadian Ingersoll-Rand unit.
The main access to the current mine operations the trackless Los Angeles adit at the 1,870 elevation. This working has been enlarged to accommodate 20-t capacity highway-type dump trucks for ore and waste haulage from the mine. Drifts and ramps are driven at a cross-section of about 3 X 3 meters, and then enlarged to accommodate the larger dump trucks to about 4.5 X 5.0 meters in section. Most ramps are driven at a maximum gradient of 15 percent. Many areas of the mine are unsupported, but in a few places, shotcrete and/or rock bolts and wire mesh or combinations of the same have been installed. In heavy ground areas, it has been necessary to install steel arches with timber lagging. FMS develops most of its short raises (<60 meters) by conventional methods, and most raises are driven at a cross-section area of about 1.5 X 1.5 meters. Historically long ore and waste pass raises, ventilation raises, etc. have been developed by raise boring contractors, and FMS will continue this policy as the need arises.
Pincock, Allen & Holt | REVISED | 25.2 |
90533 February 26, 2009 |
A ramp system in the interior of the mine provides access for low-profile diesel mobile equipment up to the 2035 level and down to the 1635 level. The portion of the main ramp above the 1870 level is being enlarged to accommodate the highway-type dump trucks. Peñoles established the 1790 main rail haulage level (from the María Isabel Shaft) to the stoping and exploration areas northeast of the shaft. In addition a rail level was also developed at the 1635 level. Both the rail levels are still in use. A longitudinal section of the mine with major shafts, and levels are included in Figure 9-2 of this report.
Mining operations at La Encantada mine are partially mechanized. Drilling of headings for both development and stoping is accomplished using pneumatic hand-held jackleg machines. Loading and tramming is done with diesel-powered, low profile front-end loaders (load-haul-dumps, or LHDs), and haulage is usually with highway-type diesel rear-dump trucks, or battery powered rail haulage trains.
Before FMS acquired La Encantada from the previous operator, Desmín, little exploration and development work had been done in the mine. Since taking over the operation in November 2006, FMS has undertaken an intensive exploration and development effort. As stated above, some mine workings are being slashed out to accommodate highway-type dump trucks, but the advance for these is not included in the development totals.
A diagram of typical drilling patterns for the different sizes of drifts and ramps driven in La Encantada Mine are shown in Figure 25-1.
During the first 9 months of 2008, the average development advance is about 570 meters per month. About 146 meters per month are classified as exploration, and the remaining 424 meters per month are for stope preparation and other development. The development totals for 2008 are shown in Table 25-1.
The principal mining method employed at La Encantada is overhand mechanized cut-and-fill (Figure 25-2), utilizing development waste for fill. Ramps are driven in the orebodies and stopes are developed from sill drifts driven in the ore zones and slashed out the full width of the ore. Stopes are drilled with jacklegs, and the main blasting agent is a commercial ammonium nitrate product, which is initiated with sausages of water-gel explosive primed with cap and fuse. Rounds are fired with Ignitacord (B-cord) as the fuse initiator. Stopes are mucked with rubber-tired 1.0 - to 3.5 yd3 Load-Haul-Dump (LHDs) machines, which also tram the broken ore to ore passes or remuck stations. Completed stope cuts are backfilled with development waste, which is passed through raises into the stope or trammed into the stope with the LHD units.
Pincock, Allen & Holt | REVISED | 25.3 |
90533 February 26, 2009 |
TABLE 25-1
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
2008 Exploration and Mine Preparation Advances (Lineal
Meters)
Month | Exploration | Mine Preparation | Total Advance |
January | 417 | 137 | 553 |
February | 208 | 139 | 347 |
March | 121 | 324 | 445 |
April | 63 | 264 | 327 |
May | 92 | 448 | 540 |
June | 170 | 521 | 691 |
July | 123 | 644 | 767 |
August | 57 | 675 | 733 |
September | 61 | 665 | 725 |
Totals | 1,312 | 3,817 | 5,128 |
A modification of overhand cut and fill stoping that has been adopted for extraction of some breccia pipes and chimney orebodies is post pillar stoping, which is essentially a room and pillar method, but on multiple horizons. Post-pillar stopes in La Encantada mine are backfilled with waste, and are mined overhand progressing from the sill level to the next level above. Most development ramps for post pillar stoping are developed in waste outside the orebody. All other parameters for stoping the post pillar areas are the same as for a standard mechanized overhand cut and fill stope. A diagram of a typical La Encantada post pillar stope is shown in Figure 25-3.
Stope production is about 11,200 tonnes per month, and there are currently about 15 stopes in production. The monthly mine production for 2008 is shown in Table 25-2.
TABLE 25-2
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
Mine Production for 2008 (wet metric tonnes)
Month | Ore from Stopes | Ore from Development | *Total Ore Mined | Average Head Grade |
January | 7,639 | 5,997 | 13,635 | 382 |
February | 11,207 | 2,634 | 13,840 | 344 |
March | 13,282 | 2,661 | 15,942 | 304 |
April | 11,471 | 1,717 | 13,187 | 344 |
May | 13,834 | 2,182 | 16,015 | 302 |
June | 13,110 | 4,374 | 17,483 | 384 |
July | 11,089 | 5,272 | 16,360 | 298 |
August | 9,733 | 4,963 | 14,695 | 314 |
September | 10,373 | 4,795 | 15,167 | 302 |
Totals | 101,734 | 34,591 | 136,326 | 330 |
*Totals will not coincide with totals for process due to moisture content of mine ore, which is normally < 6 percent.
Much of La Encantada mine development and stoping work is done by outside contractors, using company equipment. Mucking and haulage operations are done with company crews, and maintenance and other mine services are also done with company personnel. If the company does not have sufficient personnel to operate the mobile mucking and haulage equipment, the contractors will operate the equipment for extra fees. Ore haulage to the mine patios is done with contractor dump trucks, and ore transfers from the patios to the mill crusher bins are also done with outside contractors using their own trucks.
Pincock, Allen & Holt | REVISED | 25.6 |
90533 February 26, 2009 |
FMS plans to eventually reinitiate extraction of La Prieta and La Escondida abandoned chimneys, which were first mined by caving methods by Peñoles in the early years of the mine operation. The workings for the extraction of both chimneys caved in and were lost, with much waste rock material dumped into the glory-holes which had holed through to the surface. The purpose of the waste rock was to stabilize the areas proximal to the chimneys. Some ground movements have occurred in the form of concentric cracks around the ore boundaries of the chimneys, and since the chimneys are situated very near to both the main production shafts, ground movements could affect the stability of these installations. In fact some cracks in the walls of hoist room of the San Francisco shaft have been noted, apparently as a result of caving of the chimneys. Extraction of remnants left in these chimneys is technically possible, but should be delayed until the two shafts are no longer required for production or service. PAH recommends that FMS commission an updated geotechnical study and evaluation of the old mining areas near the shafts, so that any potential problem will be revealed and mitigation steps taken.
Mine ventilation is through natural air flows into and out of the mine. The maximum intake airflow is about 40,000 ft³/min. (25 m³/sec.), which is actually air flowing into the upper part of the mine through old mine workings. The maximum exhaust air flow is about 88,000 ft³/min. (54 m³/sec.) through the Los Angeles Adit level (1865 level), which is above most of the current active mining levels. From Figure 25-4 it can be appreciated that the air flows in most of the mine are very small. Although aided by using auxiliary axial fans, there is much heat buildup and stagnant air in many of the active mine workings. This problem is compounded by the use of diesel mobile equipment in the mine. The ventilation system requires a substantial up grade, and First Majestic should commission a ventilation study with independent experts, and then proceed to install major fan(s), booster fans and air-flow regulators to conduct much greater volumes of fresh air into the mine. PAH recommends that FMS commission an in-depth study of the ventilation system as a first step toward upgrading it.
A separate mine dump recovery effort continues at the mine site. This operation consists of the excavation and screening of old dump material from the previous operations, and transporting the screened product to the mill ore bins as supplemental mill feed material. The company uses a portable screening plant for the operation and the recovery operation is conducted by a combination of company operators and contractors. This material has been viable if screened to remove coarse waste material, and screened material recovered and processed totaled 42,154 tonnes at an average grade of about 119 gpt Ag during the first nine months of 2008. A summary of the month by month screened dump material recovered and processed during the first nine months of the year is shown in Table 25-3.
The mine currently operates on two 12-hour shifts per day, 7 days per week. Crews currently work two weeks at site with one week off. Both contractor crews and company personnel work the same shift schedule. Most company and contractor personnel live in the town of Muzquiz, Coahuila, which is situated about 210 km on paved highways to the northwest of the La Encantada Mine.
Pincock, Allen & Holt | REVISED | 25.8 |
90533 February 26, 2009 |
TABLE 25-3
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
Mine Dump Production for 2008 (dry metric tonnes)
Month | Ore Mined & Milled | Average Grade |
(tonnes) | (gpt Ag) | |
January | - | - |
February | - | - |
March | 3,280 | 155 |
April | 8,229 | 118 |
May | 6,859 | 108 |
June | 3,799 | 159 |
July | 6,270 | 119 |
August | 7,558 | 107 |
September | 6,158 | 101 |
Totals | 42,153 | 119 |
The company is currently transporting many personnel to and from Muzquiz to the mine site in a company bus. Peñoles constructed and maintained about 180 houses, as well as a primary school, stores and recreational facilities in the proximity of the mine site, and FMS has refurbished some of the housing and ancillary facilities to accommodate the workforce in company-controlled living quarters: presently much of the housing is occupied by contractor personnel, who are working on construction of the new 3,500-tpd cyanide plant.
The current mine workforce as of September 30, 2008 totals 490 people including contractors. There are currently 123 contractors on site, who are engaged in the new cyanide plant construction. A summary of personnel at La Encantada as of the end of September is shown in Table 25-4.
The operations budget for the first 9 months of 2008 is for milling of 136,816 tonnes from the mine and 53,734 tonnes from the old mine dumps. The average grades to the mill are budgeted at 345 gpt Ag for the mine and 104 gpt Ag for the dumps. The actual mine tonnes milled through the nine-month period total 136,327 tonnes and actual grades through the first 9 months of 2008 have averaged 352 gpt Ag. The actual mine dump tonnes removed and processed for the first 9 months of 2008 total 42,154 tonnes at an average grade of 119 gpt Ag. A summary of the 2008 mining and milling budgets for both the underground mine and the surface mine dump recovery is found in Table 25-5.
25.3 Mine Equipment
Most of the mine equipment used at La Encantada was inherited from the previous operator; Desmín and Desmín acquired most it from Peñoles. As can be appreciated from the table below, much of the mine mobile equipment fleet is very old, and FMS management has started a program of replacing much of the older equipment in the fleet.
Pincock, Allen & Holt | REVISED | 25.10 |
90533 February 26, 2009 |
TABLE 25-4
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
La Encantada Mine Manpower, Including Contractors (September 30, 2008)
Department & Category | Company | Mine Contractors |
Totals | |
Hourly | Staff | |||
SITE ADMINISTRATION Manager & General Office Safety & Environment Sub-Total |
7 2 9 |
13 2 15 |
20 4 24 |
|
MINE Miners, helpers, etc. Equipment operators, etc. Supervision, admin. Sub-Totals |
36 36 |
6 6 |
148 5 153 |
148 36 11 195 |
MINE TECHNICAL SUPPORT Engineering & Planning Geology Sub-Total |
5 2 7 |
1 7 8 |
6 9 15 |
|
MINE DUMP RECOVERY Dump recovery Supv. & Admin. Sub-Total |
5 5 |
1 1 |
0 |
5 1 6 |
MILL & PROCESS PLANT Mill & Plant Assay Laboratory New mill plant construction Sub-Total |
36 6 42 |
5 2 4 11 |
123 123 |
41 8 127 176 |
MAINTENANCE Mine & plant maintenance Supv. & Administration House keeping & construction Sub-Total |
38 38 |
7 7 |
2 27 29 |
38 9 27 74 |
TOTALS | 137 | 48 | 305 | 490 |
In fact the company has a purchase agreement with a major supplier, Sandvik, to acquire new modern mobile mine equipment. In addition to supplying the equipment, Sandvik contractually agrees to maintain it. The 2008 mine capital expenditures program included purchase of mobile equipment units in several sizes, ranging from 1.0 - -yd3 to 3.5 -yd3 capacity, of primarily diesel-powered LHDs. A summary of La Encantada mine equipment is shown in Table 25-6.
25.4 Mineral Processing Plants
25.4.1 Flotation Plant
Principal parameters of the flotation ore processing plant, including concentrate freight, smelting and refining values, are presented in Table 25-7 and a listing of the principal equipment is shown in Table 25-8. A general flow diagram of the plant is provided in Figure 25-5 and a more detailed flow diagram of the flotation section is provided in Figure 25-6. The plant was constructed in 1973 and at that time incorporated magnetic separation. In 1977 the plant was modified to convert it to flotation separation.
Pincock, Allen & Holt | REVISED | 25.11 |
90533 February 26, 2009 |
TABLE 25-6
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver Mine
Summary of Major Mine Equipment for Encantada Mine
MOBILE EQUIPMENT | ||||
No.of Units | Description of Unit | Make & Model | Size or Other | Date(s) Acquired |
1 | LHD (load-haul-dump) | Wagner Micro-Scoop (Atlas Copco) | ½ yd3 | 2007 |
2 | LHD (load-haul-dump) | Wagner ST-1A (Atlas Copco) | 1 yd3 | 1995 |
2 | LHD (load-haul-dump) | Wagner ST-2D (Atlas Copco) | 2yd3 | Unknown |
2 | LHD (load-haul-dump) | Wagner ST-2D (Atlas Copco) | 2yd3 | 1989 |
2 | LHD (load-haul-dump) | Wagner ST-2D (Atlas Copco) | 2yd3 | 1995 & 1996 |
2 | LHD (load-haul-dump) | Wagner ST-2D (Atlas Copco) | 2yd3 | 1998 |
1 | LHD (load-haul-dump) | Tamrock Toro (Sandvik) | 1yd3 | 2007 |
1 | LHD (load-haul-dump) | Tamrock Toro (Sandvik) | 1½ yd3 | 2007 |
1 | LHD (load-haul-dump) | Tamrock Toro (Sandvik) | 2yd3 | 2007 |
1 | LHD (load-haul-dump) | Tamrock Toro (Sandvik) | 4yd3 | 2007 |
1 | Mine Truck-Teletram | EJC (Sandvik) | 10 tonnes | 2000 |
1 | Mine Truck-Teletram | EJC (Sandvik) | 13-tonnes | 2007 |
1 | Electro-Hydraulic Drill Jumbo | Tamrock (Sandvik) | Single boom | Unknown |
2 | Diesel Locomotives | Plymouth | 8 tonnes | 1997 |
1 | Front-End Loader | Caterpillar 938-G | 3.0 yd3 | 2005 |
1 | Front-End Loader | Michigan M-75 | 2½yd3 | Unknown |
1 | Front-End Loader | Caterpillar 928-G | 2.5yd3 | 1998 |
1 | Mine Tractor | Ford-New Holland 5610 | NA | 1995 |
1 | Mine Tractor | Ford New Holland 6600 | NA | Unknown |
1 | U/G Road Grader | Huber F-1700 | ? | 1979 |
15 | Rail Mine Cars | Granby-Type | 2.8 M3 Each | Unknown |
MINE HOISTS | ||||
1 |
Two-Drum Ore Hoist MARIA ISABEL SHAFT |
Canadian Ingersoll-Rand Motor - 500 hp, 2200 v, 705 rpm |
72- X 54-in Drums 450 Meters, 11/8-in CABLES |
Unknown |
1 |
One-Drum Man Hoist MARIA ISABEL SHAFT |
Vulcan Ironworks Motor - 125 hp, 440v, 705 rpm |
Drum Size - N.A. 450 Meters, 1¼-in.Cable |
Unknown |
1 |
Two-Drum Ore Hoist SAN FRANCISCO SHAFT |
Canadian IngersollL-Rand Motor - 400 hp, 2300v, 505 rpm |
72-X54-in Drums 450 Meters, 11/8-in Cables |
Unknown |
MINE STATIONARY AIR COMPRESSORS | ||||
1 |
Air Compressor |
Ingersoll-Rand 440 hp, Reciprocating, XLE |
2,400 cfm |
Unknown |
1 |
Air Compressor |
Sullair 350 hp, Screw, 25-300L |
1,600 cfm |
Unknown |
PNEUMATIC DRILLING EQUIPMENT | ||||
10 | Stoper Rock Drills | Mid-Western Machinery | N.A. | Unknown |
2 | Jackleg Rock Drills | Gardner-Denver, 58F | N.A. | Unknown |
16 |
Jackleg Rock Drills |
Refacciones Pneumaticas De San Luis Potosi, S.A. |
N.A. |
Unknown |
DIAMOND DRILLING EQUIPMENT | ||||
1 | U/G Diamond-Drill Rig | Diamec Model 250 (Atlas-Copco) | Wireline | Unknown |
OTHER MINE EQUIPMENT | ||||
1 | Mine Ventilation Fan | Spendrup | 350 hp, 3,500 m3 permin. | Unknown |
2 | Mine Dewatering | Gardner-Denver | Duplex, 30 hp electric motor | Unknown |
2 | Mine Dewatering | Sulzer | 300hp, 23.6 l/sec. | Unknown |
1 | Mine Dewatering | Unknown | 40 hp electric motor | Unknown |
1 | Mine Pickup | GMC, Series 1 GTC C | Diesel pickup | 1995 |
Pincock, Allen & Holt | REVISED | 25.13 |
90533 February 26, 2009 |
TABLE 25-7
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
Flotation Plant, Principal Parameters
Parameter | Units | Mine | Dumps | Combined |
Plant Capacity | ||||
Annual | thousand tonnes/year | 300 | ||
Daily | tonnes/day | 800 | ||
Actual Throughput Rate | ||||
Annual | thousand tonnes/year | 180 | 55 | 235 |
Daily | tonnes/day | 500 | 150 | 650 |
Ore Grade | ||||
Silver | grams/tonne | 350 | 120 | 300 |
Lead | percent | 2.5 | 1.5 | 2.3 |
Recovery | ||||
Silver | 60 | 55 | 60 | |
Lead | 25 | 25 | 25 | |
Concentrate Grade | ||||
Silver | grams/tonne | 8,000 | 4,500 | 7,500 |
Lead | percent | 25 | 25 | 25 |
Concentrate Quantity | dry tonnes/year | 5,500 | ||
Primary Grind | percent minus 200 mesh | 55-60 | ||
Plant Operating Cost | $/tonne ore | 6.32 | ||
FSR Values | ||||
Freight cost | $/dry tonne concentrate | 109 | ||
Smelting cost | $/dry tonne concentrate | 505 | ||
Refining cost | $/payable kg silver | 48 | ||
Payables | ||||
Silver | percent | 95 | ||
Lead | percent | 90 |
TABLE 25-8
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
Flotation Plant, Principal Equipment List
Item |
Type/Size |
Qty. Oper. |
Qty. Instal. |
Coarse ore bin | 100-tonne capacity, stationary grizzly | ||
on top with 12-inch openings | 1 | 1 | |
Primary crusher | Jaw, 24- x 36-inch | 1 | 1 |
Vibrating screens | 6- x 14-ft, 3/8-inch openings | 2 | 2 |
Secondary crusher | Cone, 4-1/4-ft | 1 | 1 |
Crushed ore silos | 500-tonne capacity | 2 | 2 |
Ball mill | 9.5-ft dia. x 11-ft long, overflow | 1 | 1 |
Cyclone feed pumps | 1 | 2 | |
Cyclones | 20-inch dia. | 1 | 2 |
Sulfide flotation cells | Galigher, 100-ft3 | 12 | 12 |
Oxide flotation cells | Galigher, 100-ft3 | 10 | 10 |
Tailings thickener | 125-ft dia. | 1 | 1 |
Concentrate thickener | 50-ft dia. | 1 | 1 |
Concentrate filter | Larox pressure filter | 1 | 1 |
Pincock, Allen & Holt | REVISED | 25.14 |
90533 February 26, 2009 |
Ore is from two sources: from the underground mine and from old mine dumps with the mine contributing about 71 percent of the feed while the processing of dump material accounts for the rest. The dump rock is screened ahead of the plant which results in upgrading the rock to about twice the grade of unscreened material. Mine and dump ore are not mixed; they are campaign processed through the plant.
The plant is a simple flotation plant in a single-line arrangement. Crushing is accomplished using two stages of crushing closed on the second stage, and the ore is milled in a single ball mill closed with a cyclone. The mill is rubber lined and is charged with 2-1/2-inch diameter grinding balls. Sulfide minerals and oxide minerals are floated sequentially and both circuits incorporate just one stage of cleaning.
Concentrates from both the sulfide and oxide circuits are combined in a concentrate thickener. Thickened concentrates are filtered on a pressure filter press and the filtered concentrate, which contains about 20 percent moisture, is sun dried on a concrete patio to about 10 percent moisture, then trucked to the Peñoles smelter at Torreón.
Tailings are thickened and then pumped to a nearby tailings containment. Tailings thickener overflow and the decant water from the tailings containment are pumped to a recycle-water tank and reused in the process.
25.4.2 Cyanidation Plant
La Encantada is currently building a 3,500 tonne per day cyanidation plant. The plant is expected to commence operations in the April 2009. Feed to the plant will be reclaimed tailings and the mined ore and waste dump rock currently processed in the existing flotation plant. The crushing and grinding of the mined ore and waste dump rock will continue to be done in existing crushing and grinding equipment. The cyanidation plant will incorporate a mill for mild regrinding of reprocessed tailings.
Principal parameters of the cyanidation plant are presented in Table 25-9 and a listing of the principal equipment is shown in Table 25-10. A general flow diagram of the plant is provided in Figure 25-7 and the layout of the plant is shown in Figure 25-8.
Tailings from the new plant will be pumped to new lined tailings containment in a small valley below the plant. Decant water from the tailings will be pumped back to the plant and reused in the process.
25.5 Infrastructure
The infrastructure for La Encantada was very well developed by the previous operators, especially Peñoles. The operations support facilities, located near the plant, include administrative offices, a medical clinic, warehouse, airstrip, assay laboratory, power generation plant, fuel storage facilities, maintenance shops, mine compressor building, surface maintenance shop, mine dry, water storage tanks, employee hotel and dining hall, contractor offices and security guard shack.
Pincock, Allen & Holt | REVISED | 25.16 |
90533 February 26, 2009 |
TABLE 25-9
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
Cyanidation Plant, Principal Parameters (FMS Cash Flow Model)
Parameter |
Units |
Mine & Dumps |
Tailings No. 1 |
Tailings No. 2 |
Combined |
Plant Throughput | |||||
Annual | thousand tonnes/year | 200 | 180 | 620 | 1,000 |
Daily | tonnes/day | 700 | 628 | 2,172 | 3,500 |
Ore Grade, Silver | grams/tonne | 350 | 72 | 168 | 187 |
Silver Recovery | percent | 78 | 52 | 48 | 59 |
Silver Production | |||||
Annual | tonnes/year | 110 | |||
Annual | thousand ounces/year | 3,600 | |||
Particle Size | |||||
Feed | percent minus 200 mesh | ~70 | |||
Product | percent minus 200 mesh | ~85 | |||
Power Consumption | kilowatt-hours/tonne | 4.0-4.5 | |||
Plant Operating Cost | $/tonne ore | 6.60 |
TABLE 25-10
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
Cyanidation Plant, Principal Equipment List
Item |
Size |
hp each |
Qty.
Oper. |
Qty.
Instal. |
Semi-rich solution tank | 11.5-m dia. x 12.6-m high | 1 | 1 | |
Water monitor pumps | 75 | 2 | 3 | |
Water monitors | 2 | 2 | ||
Repulping bins | 2 | 2 | ||
Vibrating screens | 10 | 2 | 2 | |
Slurry mix tanks | 9-m dia. x 10-m high | 60 | 2 | 2 |
Attritioning tanks | 5-m dia. x 2-m high | 100 | 2 | 2 |
Ball mill | 10.5-ft dia. x 14-ft long | 900 | 1 | 1 |
Cyclone feed pumps | 200 | 2 | 2 | |
Cyclones | 20-inch dia. | 4 | 4 | |
Primary thickener | 125-ft dia. x 10-ft high | 13 | 1 | 1 |
Leach tanks | 30-ft dia. x 43-ft high | 60 | 17 | 17 |
Intermediate thickener | 125-ft dia. x 10-ft high | 13 | 1 | 1 |
CCD thickeners | 125-ft dia. x 10-ft high | 13 | 4 | 4 |
Semi-rich solution tank | 12-m dia. x 13-m high | 1 | 1 | |
Dirty pregnant solution tank | 12-m dia. x 13-m high | 1 | 1 | |
Clarifying filters | 2 | 3 | ||
Clean pregnant solution tank | 12-m dia. x 13-m high | 1 | 1 | |
Deoxygenation towers | 2 | 2 | ||
Vacuum pumps | 2 | 2 | ||
Zinc dust feeders | 2 | 2 | ||
Press feed pumps | 2 | 3 | ||
Precipitate filter presses | 4 | 4 | ||
Precipitate dryer | 1 | 1 | ||
Barren solution cistern | 1 | 1 | ||
Emergency pond | 1 | 1 |
Pincock, Allen & Holt | REVISED | 25.18 |
90533 February 26, 2009 |
The Maintenance Department operates from the surface shops, and also from an underground shop (840 level), located near the center of the mine. Road maintenance is done with a fleet of company tractors, road grader and wheel loaders. Dump trucks for ore haulage and road maintenance are largely vehicles contracted locally. The company has a passenger bus for transporting operations personnel to and from the town of Muzquiz, where most employees have homes.
The company also has a town constructed by Peñoles, and which is partially occupied at this time. The town site has 180 housing units of which 80 percent are occupied. There is also a kitchen/dining room for salaried staff and some contractor managers and visitors, a primary school, a church, a store, recreational facilities, etc.
The electric power for the operation and supporting infrastructure is generated on-site. The power generation plant consists of three General Motors 3,250 KVA diesel-powered motor generators. In addition there are two 1,000 KVA CAT D399 motor-generator sets for site power, when the mill and process plant are idle. Power consumption is presently about 800,000 kilowatt-hours per month. The new cyanide leach plant will have its own generating plant.
Potable water for the offices and employee housing is derived from a well in the mine, which penetrates below the water table. The industrial water for the mine and plant is obtained from a series of wells located about 25 kilometers from the site. A system diagram for the industrial water is shown in Figure 25-9. This water is pumped to and stored in a number of storage tanks located throughout the plant and mine site.
Communications to and from La Encantada is via satellites, both for wireless internet information systems, and also for the telephone system. Currently the telephone system has two lines. La Encantada has a site radio system for instant communications between all Supervisors and Managers, and all surface vehicle operators also have radio communication capabilities.
There is a FMS owned airstrip located in the broad valley to the northwest of the mine site. This strip is suitable for light planes, and is used for flying in supplies, or for transporting mine personnel, visitors and others into and out of La Encantada, and other nearby locations. The airstrip is 1,200 meters long, 17 meters wide, and has a gravel surface.
The site is connected with the national highway system and, although in a remote location, La Encantada is reasonably accessible. The access to the mine from the town of Muzquiz, Coahuila, which lies to the northeast of La Encantada, accessible via a 45 kilometers of gravel road, and then another 170 kilometers on a paved highway to Muzquiz.
Pincock, Allen & Holt | REVISED | 25.21 |
90533 February 26, 2009 |
25.6 Product Marketing
FMS has a purchase agreement with MET-MEX Peñoles located in the city of Torreón, State of Coahuila, México. The purchase agreement establishes the obligation to sell all mineral production from La Encantada mine to the Peñoles smelter assuming other more competitive rates are not available to FMS. This, however, is the natural market for concentrates since the MET-MEX Peñoles smelter is the closest such facility for shipping La Encantada concentrates. The contract between La Encantada and Peñoles for sales of bulk flotation concentrate is typical for this product.
La Encantada purchase contract of concentrates with Peñoles includes typical conditions and related charges as follows:
25.7 Environmental Safety Review
Minera La Encantada has been operating the La Encantada mine since the early 1970s with the necessary land-use and water extraction permits in effect for the operation. FMS has purchase the land surface rights, under expropriation procedures from Ejido Tenochtitlán, where the camp, water wells, mine and plant installations are located to better manage the property. Through the years and changes in the regulatory framework, La Encantada has been required to update the necessary operation permits.
In April 24, 2007 La Encantada presented a notification of reactivation of operations at the mine to the National Water Commission (C.N.A.), to SEMARNAT, to Secretaría del Trabajo y Previsión Social, and to PROFEPA. La Encantada mine was declared in suspension of activities by Peñoles in 2003.
PAHs environmental and safety review consisted of discussions with FMS COO Ing. Ramón Dávila Flores, and mine manager and supervisors, Ing. Salvador Hernández, Manager of Operations and other personnel. PAH visited the site to observe the current site safety and environmental conditions and to identify any potential liabilities having significant economic impacts, and a briefly reviewed file records provided to PAH during the site visit. PAHs assessment was not intended as an environmental and safety compliance audit, although prudent practices were considered in the review. In PAHs opinion, La Encantada is in compliance with regulatory requirements, which are current accoprding to Legal Opinion issued by Durango-based Legal Firm of Lic. Carlos Galván Pastoriza issued on October 31, 2008, and document on Environmental and Operating Permits issued by Mr. José Luis Hernández Santibañez, Corporate Manager on Environmental and Permitting for FMS, in a document issued on October 31, 2008 showing current status and confirmation of the required permits and authorizations.
Pincock, Allen & Holt | REVISED | 25.23 |
90533 February 26, 2009 |
In general, surface disturbance related to mining is limited to the access road to the mining levels, waste rock dumps at each portal, and auxiliary support areas. Development waste rock is used for fill inside the mine and limits the size of waste rock dumps at the surface. Most of these activities are carried out on land owned by La Encantada. No acid rock drainage (ARD) is produced from the mine workings.
PAH noted no visible evidence of ARD on the active and historic tailings deposition areas or spent heap leach pile. The surface of the active tailings impoundment is wetted, which controls fugitive dust emissions.
The grinding area, agitated leach tanks, wash thickeners, cyanide mix tank, and several other process vessels in the mill area have spill containment. There are minimal stormwater control measures to route uncontaminated runoff away from the mill or to collect and contain stormwater runoff from around the mill site.
La Encantada has good control of the storage of hazardous chemicals and lubricants at the mill site and has installed concrete pads and fenced areas for drums.
Although Mexican environmental legislation is not explicit in the requirements for remediation, reclamation, and closure, the SEMARNAP expresses concern for the preservation and restoration of the environment and natural ecosystems in its environmental management guidance for industry. In fact, SEMARNAP recommends that facilities establish and implement a program for remediation of spills and releases to the environment.
La Encantada has not supplied to PAH the estimated costs for reclamation and mine closure of the mine or mill and tailings containment areas; however, PAH considers the costs will be low because La Encantada owns most of the surface rights where the installations and mine are located.
PAHs estimate for the costs required to comply with and remediate the environmental issues for the project is approximately $150,000 in addition to the salvage value of plant and mine equipment. These costs are based on PAHs experience in mining projects in México, and are not the result of detailed analysis. Actual costs will depend on site conditions and impacts from the operation, regulatory requirements at the time of compliance, and corporate environmental management standards.
25.8 Economic Analysis
25.8.1 Capital Costs
The FMS capital expenditures for January to September 2008 total $11.82 million. The 5-year capital budget (2009 thru 2013) is $26.1 million including costs for construction of a new 3,500-tpd cyanide plant, existing mill and flotation plant upgrades, power plant upgrades, mine equipment additions and replacements, exploration and mine development programs and infrastructure upgrades and additions. Major capital expenditures in the program registered for the first nine months of 2008 includes expenditures for exploration programs, expenditures for certain mine development, some mine equipment purchases, improvements to the existing process plant and construction of the new 3,500-tpd cyanide process plant. The 2008 actual capital expenditures for the first nine months of 2008 versus the Budget are shown in Table 25-11, and the capital investment schedule for la Encantada five-year plan is shown in the Table 25-12.
Pincock, Allen & Holt | REVISED | 25.24 |
90533 February 26, 2009 |
TABLE 25-11
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
2008 Capital Expenditures
Category | Actual | Plan | Difference |
Mine Development | 3,759,840 | 3,711,875 | (47,965) |
Sandvik (Mining Equipment) | 838,692 | 3,667,092 | 2,828,400 |
3,500-tpd Cyanide Plant Project | 6,998,376 | 13,300,000 | 6,301,624 |
Fixed Assets and Other | 419,279 | 346,560 | (72,719) |
Total | $12,016,187 | $21,025,527 | $9,009,340 |
TABLE 25-12
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
Estimated Capital Expenditures Summary (5 years)
2009 | 2010 | 2011 | 2012 | 2013 | TOTALS | |
New 3,500-TPD Cyanide Plant
Sub-Total |
8,212,059 8,212,059 |
8,212,059 8,212,059 | ||||
Exploration & Development
Diamond Drilling Development & Exploration Sub-Total |
600,000 2,400,000 3,000,000 |
600,000 2,400,000 3,000,000 |
600,000 2,400,000 3,000,000 |
600,000 2,400,000 3,000,000 |
600,000 2,400,000 3,000,000 |
3,000,000 12,000,000 15,000,000 |
Mine Equipment Scooptrams Trucks Auxilliary Equipment Compressors Safety Equipment & Mine Rescue Sub-Total |
200,000 75,000 100,000 25,000 400,000 |
200,000 75,000 100,000 25,000 400,000 |
200,000 75,000 100,000 25,000 400,000 |
200,000 75,000 100,000 25,000 400,000 |
200,000 75,000 100,000 25,000 400,000 |
1,000,000 375,000 500,000 125,000 2,000,000 |
Construction & Plant Improvements
Upgrade Flotation Plant Upgrade Power Plant Buildings and Offices Sub-total |
100,000 34,660 134,660 |
100,000 34,660 134,660 |
100,000 34,660 134,660 |
100,000 34,660 134,660 |
100,000 34,660 134,660 |
500,000 173,300 673,300 |
Mining Rights Annual Payments Sub-Total |
40,000 40,000 |
40,000 40,000 |
40,000 40,000 |
40,000 40,000 |
40,000 40,000 |
200,000 200,000 |
TOTALS | 11,786,719 | 3,574,660 | 3,574,660 | 3,574,660 | 3,574,660 | 26,085,359 |
Pincock, Allen & Holt | REVISED | 25.25 |
90533 February 26, 2009 |
25.8.2 Operating Costs
La Encantada operating costs for the first nine months of 2008 have averaged $51.69 per tonne of ore processed, inclusive of dump material, which equates to a cost per ounce of silver of $9.09. The costs include downstream concentrate freight and processing costs of about $21.54 per tonne milled or $3.35 per ounce of silver recovered. The average combined operating cost for 2008 has averaged about $51.69 per tonne milled. A summary of the combined mine and dump recovery operating costs for the first nine months of 2008 is found in Table 25-13.
TABLE 25-13
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
Summary of Unit Operating Costs for 2008, Jan - Sept ($US )
Cost Area |
Total Cost ($000's) |
*Cost per Tonne |
**Cost per Oz. Ag |
U/G Mine | 1,912 | 10.71 | 1.67 |
Mill & Concentrator | 1,070 | 6.00 | 0.93 |
Site G&A | 2,401 | 13.45 | 2.09 |
Conc. FSR | 3,844 | 21.54 | 3.35 |
Totals | $9,226 | $51.69 | $8.05 |
*Based on 135,109 tonnes from U/G mine
and 42,153 tonnes from dump recovery or 177,262 tonnes.
**Based on 1,014,813 equivalent oz Ag from U/G mine and 131,406
equivalent oz Ag from dump recovery or 1,146,219 equivalent oz.Ag.
The average mine-only operating cost is $55.01 per tonne, and also includes costs for concentrate freight to the Peñoles smelter and the downstream processing of the silver-lead concentrates. The site-only operating cost for the mine generated ore has averaged about $33.47 per tonne, and the total cost per ounce of silver obtained from mine ore has averaged $4.43 per oz Ag for 2008. The downstream concentrate freight and smelting and refining costs are $21.54 per tonne or $2.85 per oz Ag for the first nine months of 2008. A summary of the mine-only operating costs is shown in Table 25-14.
TABLE 25-14
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
Summary of Unit Operating Costs for First 9 Months of 2008; U/G Mine Only
($US)
Cost Area | Total Cost ($000's) | *Cost per Tonne | **Cost per Oz. Ag |
U/G Mine | 1,912 | 14.02 | 1.86 |
Mill & Concentrator | 817 | 6.00 | 0.79 |
Site G&A | 1,834 | 13.45 | 1.78 |
Total Direct Costs | 4,563 | 33.47 | 4.43 |
***Concentrate Freighting, | |||
Smelting & Refining | |||
Freighting | 121 | 0.89 | |
Smelting and Refining | 2,815 | 20.65 | |
Total Conc. FSR | 2,936 | 21.54 | 2.85 |
TOTALS | $7,499 | $55.01 | $7.28 |
*Based on 135,326 tonnes from U/G Mine
*Based on 923,754 oz Ag + 106,378 oz Ag from Pb credit = 1,030,132
***Based on September 2008 concentrate grades & FSR from mine &
smelter
Pincock, Allen & Holt | REVISED | 25.26 |
90533 February 26, 2009 |
The average costs for extraction and processing of the old dump material for the first nine months of 2008 are $40.98 per tonne, or $14.88 per oz Ag produced. The site-only cost for extraction, screening, milling and processing of the old mine dumps is $19.45 per tonne, or $7.06 per ounce. Concentrate freight and downstream smelting and refining for the dump material have averaged an additional $21.54 per tonne of ore extracted.
Table 25-15 is a summary of the operating costs for the first nine months of 2008 for the dump recovery effort.
TABLE 25-15
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada Silver
Mine
Summary of Unit Operating Costs for First 9 months of 2008; Dump
Recovery Only ($US)
Cost Area | Total Cost ($000's) | *Cost per Tonne | **Cost per Oz. Ag |
Dump Recovery | - | 0.00 | 0.00 |
Mill & Concentrator | 253 | 5.99 | 2.18 |
Site G&A | 567 | 13.45 | 4.88 |
Total Site Operating | 820 | 19.44 | 7.06 |
***Concentrate Freighting, | |||
Smelting & Refining | |||
Freighting | 47 | 1.12 | 0.41 |
Smelting and Refining | 861 | 20.42 | 7.41 |
Total Conc. FSR | 908 | 21.54 | 7.82 |
TOTALS | $1,728 | $40.98 | $14.88 |
*Based on 42,153 tonnes milled from dumps
**Based on 91,059
oz. Ag + 25,028 equiv. oz. Ag from Pb credit = 116,087 equiv. oz. Ag from
Dumps
***Based on September 2008 concentrate grades & FSR from dump recovery
The company is currently constructing a 3,500-tpd mill and cyanide processing plant, mainly for reprocessing at least 5.0 million tonnes of old tailings, stored below the mine site. The company developed a cost per tonne, and metallurgical recoveries for recovery of silver-and small amounts of gold from the old tailings material. FMS plan to produce silver/gold precipitates in the plant, and are still evaluating shipping the precipitate to La Parrilla for smelting into bullion bars, or producing their own bullion bars at La Encantada.
First Majestic has estimated the all-in direct operating costs for tailings recovery, reprocessing, ancillary services and downstream costs at about $17.00 per tonne processed. A breakdown of this cost estimate is shown in Table 25-16.
25.8.3 Economic Analysis
A simplified production plan has been prepared by First Majestic, and is presented as Table 25-17 and a Life of Mine cash-flow is shown in Table 25-18. First Majestic has predicated this cash flow on bringing the new 3,500-tpd mill and cyanide plant on stream during April 2009, after which the shipment of flotation concentrates to outside smelters will cease, and mine ore and old tailings will be processed in the new plant. Bullion precipitates will be produced in the new plant and these will be shipped to La Parrilla Mine for processing into bullion bars. The First Majestic Life of Mine production plan, included in the cash flow, covers the period from January 2009 through December 2015. However, the Proven and Probable ore reserves for the underground mine will be exhausted by 2013 at which time the production for the subsequent years will be extracted from the measured and indicated resources. In the interim, it is expected that underground exploration will be advanced through both diamond drilling and drifting, and those reserves will continually be added over time. Likewise at planned production rates, the proven and probable reserve for the tailings recovery will be exhausted by 2014, and subsequently all production will be obtained from the underground mine.
Pincock, Allen & Holt | REVISED | 25.27 |
90533 February 26, 2009 |
TABLE 25-16
First Majestic Silver
Corp.
Minera La Encantada, S.A. de C.V.
La Encantada
Silver Mine
Estimated Operating Costs for Tailings Recovery Project
COST AREA | *Total Cost | Cost per Tonne | **Cost per Oz. Ag |
Mining, Haulage, Other | $3,517,650 | $4.50 | $1.93 |
Mill & Cyanide Plant | 4,299,350 | 5.50 | 2.36 |
Tailings Disposal | 1,250,720 | 1.60 | 0.69 |
Site G&A | 2,657,780 | 3.40 | 1.46 |
Sub-Total Site Operating | $11,725,500 | $15.00 | $6.44 |
Freight, Smelting & Refining (FSR) | |||
Smelting and Refining | 1,563,400 | 2.00 | 0.86 |
Sub-Total FSR | $1,563,400 | $2.00 | $0.86 |
TOTALS | $13,288,900 | $17.00 | $7.30 |
*Based on 0.781 million tonnes per year of tailings
**Based on production of 1.824 million oz. Ag per year
The basic parameters for the FMS cash flow involve the long-term silver price, which is projected as $12/ounce. The average projected long-term gold price is about $708 per oz Au, while the lead price is projected at $0.75/lb. No escalation was considered for operating costs and expenses. Reclamation expenditures are considered spent in the last three years of the period. It can be seen from the table that a net present value for the project at a 15 percent discount rate is approximately $53.0 million, and the internal rate of return (IRR) is 120.6 percent
The parameters for the plant recoveries in the 3,500-tpd mill and cyanidation plant are based on preliminary testwork. Dumps included represent 89,000 tonnes plus 57,000 tonnes of Indicated Resources. Plant operating costs used in the cash flow are calculated costs, and will not be confirmed until several months of actual operation have taken place. Therefore; PAH has predicated cut-off grades for the mine and mine dump recoveries on the basis of the current operation; i.e., continuance of milling and processing operations (Milling and Flotation) as per current practice.
Once the new plant is started up metallurgical parameters and operating and ancillary costs are well defined, First Majestic can revaluate the cut-off grades for the mine, mine dump recovery and tailing recovery based on actual operating data, and issue a new reserve/resources statement. PAH would then proceed with an updated audit, based on the material change in the operation.
Pincock, Allen & Holt | REVISED | 25.28 |
90533 February 26, 2009 |
Pincock, Allen & Holt | REVISED | 25.29 |
90533 February 26, 2009 |
Pincock, Allen & Holt | REVISED | 25.30 |
90533 February 26, 2009 |
Sensitivity analyses were performed at different discount rates and the analysis shows robust economics for La Encantada, as follows:
As expected, the project exhibits the greatest sensitivity to metal prices, followed by operating costs, and finally by capital costs. Any variances in grade or metallurgical recovery will be equivalent to similar changes in metal prices, since all three factors impact the revenue stream equally. In all cases, however, the La Encantada mine shows positive economics as measured by a cash flow exercise, except when the price of silver falls by 20 percent. Therefore, the postulated reserve position is accepted.
It can be seen from Tables 25-17 and 25-18 that there is sufficient after-tax operational cash flow in any year to adequately cover projected capital expenditures.
The mine life, including tailings recovery, based on the proven/probable reserve position, is over 4.0 years and covers production through 2013.
Pincock, Allen & Holt | REVISED | 25.31 |
90533 February 26, 2009 |
26.0
ILLUSTRATIONS
The illustrations supporting the various sections of this report are located within the relevant sections immediately following the references to the illustrations, for ease of reference. An index of tables and illustrations is provided at the beginning of this report.
Pincock, Allen & Holt | REVISED | 26.1 |
90533 February 26, 2009 |