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INVESTMENT IN MINERA SANTA CRUZ S.A. ("MSC") - SAN JOSE MINE (Details) (MSC, USD $) In Thousands, unless otherwise specified | 3 Months Ended | 6 Months Ended | 8 Months Ended | 9 Months Ended
--- | --- | --- | --- | ---
Sep. 30, 2012 | Jun. 30, 2012 | Mar. 31, 2012 | Jun. 30, 2012 | Sep. 30, 2012 | Sep. 30, 2012
Change in investment |  |  |  |  |  |
Fair value of investment in MSC from acquisition of Minera Andes | $ 261,186 |  |  |  | $ 261,186 | $ 261,186
Amortization of fair value increments | (1,597) | 1,259 | 890 | 2,149 |  | (3,746)
Net loss | 26,343 | (20,707) | (16,997) | (37,995) | 37,765 |
Reported |  |  |  |  |  |
Change in investment |  |  |  |  |  |
Amortization of fair value increments |  | 1,803 | 2,804 | 4,607 |  |
Net loss |  | (21,251) | (19,202) | (40,453) |  |
Adjustment |  |  |  |  |  |
Change in investment |  |  |  |  |  |
Amortization of fair value increments |  | (544) | (1,914) | (2,458) |  |
Net loss |  | 544 | 1,914 | 2,458 |  |
Purchase price allocation adjustment |  |  |  |  |  |
Change in investment |  |  |  |  |  |
Fair value of investment in MSC from acquisition of Minera Andes | $ 261,200 | $ 225,000 | $ 225,000 | $ 225,000 | $ 261,200 | $ 261,200

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