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PLEASE NOTE: This page is currently under construction. Please refer to the Bear Creek press release dated Monday April 20th 2009.


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Project Summary

Bear Creek identified and staked the Santa Ana Property in 2004, based on its potential to host a near-surface, bulk-tonnage silver deposit. The un-drilled prospect then covered extensive workings where colonial-era miners had exploited high-grade silver mineralization. Initial exploration by Bear Creek revealed a large silver anomaly that was subsequently determined to be at least 2.5 kilometers long by 600 meters wide. Santa Ana was the first grass-roots discovery made in the same epithermal belt now hosting the Company's advanced Corani Project.

The first two phases of wide-spaced drilling completed by Bear Creek in 2006 confirmed the presence of a significant bulk-tonnage silver deposit with many favorable features, including silver mineralization amenable to low-cost heap-leaching and open-pit mining at a low stripping ratio. A third phase of drilling is expanding the footprint of the silver mineralization, defining high-grade zones that enhance the value of the property, and providing data that continue to support the positive results of preliminary metallurgical test-work.

Santa Ana is a high-priority exploration project rapidly advancing to the development stage that still offers excellent potential for new discoveries. The project covers 1.4 square kilometers of favorable geology, of which about 50% has been tested by wide-spaced drilling.

Location and Access

The Santa Ana Property is situated in the Department of Puno near the border with Bolivia, about 200 kilometers south of the Corani Project. The project is a three-hour drive from the city of Puno, mostly by paved highway and a short distance on an upgraded gravel road.

Bear Creek controls 100% of 6,300 hectares of mineral rights covering the mineralization defined to date and potential extensions. Because the project lies within the 50-kilometre Peruvian border zone, the Company has applied and received a special decree that allows foreign company ownership within this zone.

Geology and Mineralization

Santa Ana is a volcanic-hosted, epithermal system hosting large volumes of exposed, primarily oxide silver mineralization. Mineralization is contained within numerous structural feeders and in widespread crackle breccias (with disseminated barite) that crosscut and replace bedding in the volcanic sequence. Tertiary andesite flows and pyroclastics have been intruded by sub-volcanic quartz feldspar porphyries and hydrothermal breccias. Dacite domes and breccias play an important role in ore deposition at the San Cristobal silver deposit being developed by Apex Silver Mines in neighboring Bolivia.

Bulk-tonnage silver deposits such as Santa Ana are not common, and until the discovery of San Cristobal in the 1990s, there were few geological models to guide exploration for such targets. Bear Creek's Corani Project is also hosted in a similar geological environment as Santa Ana. Shared exploration and drilling data benefit both projects.

Exploration Programs

Few early-stage exploration programs are as successful as the initial program at Santa Ana, which included geophysical and geochemical surveys, geological mapping and sampling focused on mineralized showings and shallow historic workings. This work identified coincident geophysical and geochemical anomalies where 446 rock-chip samples returned average grades of 80 g/t silver, 0.30% lead and 0.23% zinc.

A Phase I drilling program of 11 widely spaced holes in early 2006 confirmed the bulk-tonnage potential of the property while also returning significant results, notably 12 meters of 189 g/t silver at surface. The Phase II drilling program continued to establish large volumes of near-surface silver mineralization. Within a one-square-kilometer area, all but four of 28 widely spaced holes (up to 500 meters apart) intersected silver mineralization. By year-end 2006, Santa Ana had been tested by 4,311 meters of drilling in 37 holes. The average of all reported intercepts in both drill phases is 53 meters averaging 43.9 g/t silver, with many higher-grade intervals.

A 2,500-metre, Phase III drilling program began in April of 2007. By mid-May, drilling at Santa Ana totaled 5,034 meters in 42 widely spaced holes, of which 39 holes intersected mineralization. Results from the first five holes exceeded expectations by returning several high-grade intersections, prompting Bear Creek to expand the 2007 drilling program in order to test extensions of known mineralization and explore new areas with significant surface values. Highlights from this phase of drilling include: 152 meters grading 96.3 g/t silver, including 52 meters at 240 g/t silver from Hole SA-2B; and 20 meters at 128 g/t silver, including 4 meters at 416 g/t silver from Hole SA-23.

Drilling continues to expand the oxide-dominant silver mineralization and is starting to define high-grade feeder structures that represent potential underground mining targets. The 2007 work program also includes a soil-sampling program to test for blind mineralization in areas to the north, south and southwest of known mineralization.

The Santa Ana Project is advancing to the stage where a preliminary economic assessment (or scoping study) will soon be initiated in order to provide the first indication of the project's potential. The study will be based on data from ongoing exploration and drilling programs, metallurgical test-work, and environmental and socio-economic studies.

Resource Estimation

The resource estimates was updated in September of 2008 based on 47,436 meters of drilling in 260 diamond drill holes. The resource is contained with in an economic mining pit based on a $12 per ounce silver and was prepared by Independent Mining Consultants (IMC) of Tucson, Arizona, with John Marek, P.E. acting as the Independent Qualified Person under NI 43-101. The updated resource showed an almost three fold increase in measured and indicated resources over the first resource calculation and the deposit remains open in three directions.

Bear Creek Mining, Santa Ana Deposit
Mineral Resource Based on 20 g/t Cutoff and Prudent Open Pit Constraints
September 2, 2008

 

 

Contained Metal

Category

Ktonnes

Silver

Lead

Zinc

Silver

Lead

Zinc

 

 

Gm/t

%

%

Million Ozs

Million Lbs

Million Lbs

 

 

 

 

 

 

 

 

Measured

10,385

48.1

0.36

0.64

16.1

82.4

146.5

Indicated

45,592

45.1

0.33

0.56

66.1

331.7

562.9

Measured + Indicated

55,977

45.7

0.34

0.57

82.2

414.1

709.4

 

 

 

 

 

 

 

 

Inferred

23,333

50.3

0.32

0.51

37.7

164.6

262.3



The stripping ratio is approximately 1.8:1; however, the block model considers blocks with no nearby drill holes as waste and additional drilling will convert many of these blocks to resource, reducing the stripping ratio. Lead and zinc are not recovered in a heap leach; however, flotation testing will examine this up-side as higher-grade base metals are seen in several drill holes.

The resource was calculated using indicator kriging to establish the limits of mineralization and block grades were then calculated using a linear kriging method using 5-meter drill hole composites. The 20 g/t Ag cutoff was chosen based on operational assumptions substantiated by recent metallurgical test work completed at McClelland Labs and cost assumptions provided by both IMC and Resource Development Inc. (RDI) of Denver Colorado. Deepak Malhotra, PhD acted as Independent Qualified Person for process costs and recoveries.

Metallurgy

Preliminary metallurgical test-work has shown that conventional heap-leaching processing methods will likely be the best option for processing and recovering the silver found at Santa Ana deposit. A siting study has been performed by a independent engineer and it shows that there is ample room for a heap leach and could easily be constructed close to the deposit.

Bear Creek has investigated the possibility of milling and vat-leaching the "high-grade" silver mineralization encountered in the Phase III drilling program and found that high recovery can be obtained. It is possible, if additional high-grade feed can be found that the high-grade would be processed in a mill and the lower grade material would be crushed and fed to a heap-leach process. Prior to placement on the heap the tailings from the mill and the crushed low grade would be combined on the heap-leach pad in a processing method known as pulp agglomeration. Additionally the mill could be designed to process some of the very high grade base metal material using conventional flotation to recover the zinc and lead prior to placing the tailings on the heap leach pad.

A large-scale column-leach test program has been completed at McClelland Labs on typical Santa Ana material and has shown heap leach recoveries of greater than 65% for ¾ inch crushed material. The recovery of silver was still occurring when the tests were terminated and we feel that the ultimate heap leach recovery of silver would be approximately 70% in a commercial heap leaching operation.

The company has also completed several bottle-role test programs that show when the material is ground to 50% passing 200 mesh that we can expect at least 85% recovery of the silver using agitation leaching. Additionally, Bear Creek has continued to test the Santa Ana material to establish the "leachability" of the ore using a 24-hr cyanide shaker test. These tests have shown that the material remains leachable in all areas of the deposit.

Maps & Sections

  • Santa Ana Drill Summary - July 15th 2008 (XLS format)

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    :Show image 'Santa Ana Drill Hole Map -- January 21st 2009' in New Window:
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    Santa Ana Drill Hole Map -- January 21st 2009
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    :Show image 'Santa Ana Drill Hole Map - September 4, 2008' in New Window:
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    Santa Ana Drill Hole Map - September 4, 2008
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    :Show image 'Santa Ana Cross Section A-A' December 17, 2007' in New Window:
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    Santa Ana Cross Section A-A' December 17, 2007
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    :Show image 'Santa Ana Geochemistry Map Anomaly "B"' in New Window:
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    Santa Ana Geochemistry Map Anomaly "B"
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    :Show image 'Santa Ana Conceptual Cross Section' in New Window:
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    Santa Ana Conceptual Cross Section
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