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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) (USD $) | 12 Months Ended
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Dec. 31, 2012
Concentrations |
Bank account balances in excess of the federally insured limits | $ 59,700,000
Federally insured limits | $ 100,000
Stockpiles, Ore on Leach Pads, In-process Inventory, Precious Metals Inventory and Materials and Supplies: |
Period for determining current portion of stockpiles, ore on leach pad, in-process inventory and materials and supplies | 12 months
Period within which Stockpiles, ore on leach pads, in-process inventory and materials and supplies are not expected to be processed, classified as long-term | 12 months
San Jose Mine |
Proven and Probable Reserves |
Ownership interest (as a percent) | 49.00%

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