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OPERATING SEGMENT REPORTING (Details) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2012 | Sep. 30, 2011 | Sep. 30, 2012 | Sep. 30, 2011 | Dec. 31, 2011
OPERATING SEGMENT REPORTING |  |  |  |  |
Income on investment in Minera Santa Cruz S.A. | $ 11,311 |  | $ 14,759 |  |
Gold and silver sales | 456 |  | 456 |  |
Production costs applicable to sales | 119 |  | 119 |  |
Exploration costs | 6,708 | 15,115 | 28,565 | 32,650 |
Mine construction costs | 4,671 |  | 13,306 |  |
Mine development and operating costs | 2,406 |  | 8,622 |  |
Operating income (loss) | (10,554) | (21,239) | (56,817) | (44,124) |
Investment in Minera Santa Cruz S.A. | 271,180 |  | 271,180 |  |
Mineral property interests | 785,278 |  | 785,278 |  | 245,454
Total assets | 1,111,205 |  | 1,111,205 |  | 310,355
Argentina |  |  |  |  |
OPERATING SEGMENT REPORTING |  |  |  |  |
Income on investment in Minera Santa Cruz S.A. | 11,311 |  | 14,759 |  |
Exploration costs | 1,539 |  | 11,369 |  |
Operating income (loss) | 9,200 |  | 1,231 |  |
Investment in Minera Santa Cruz S.A. | 271,180 |  | 271,180 |  |
Mineral property interests | 541,702 |  | 541,702 |  |
Total assets | 831,129 |  | 831,129 |  |
Mexico |  |  |  |  |
OPERATING SEGMENT REPORTING |  |  |  |  |
Gold and silver sales | 456 |  | 456 |  |
Production costs applicable to sales | 119 |  | 119 |  |
Exploration costs | 3,847 | 10,822 | 12,394 | 22,846 |
Mine construction costs | 4,671 |  | 13,306 |  |
Mine development and operating costs | 2,406 |  | 8,622 |  |
Operating income (loss) | (12,650) | (12,196) | (38,733) | (25,728) |
Mineral property interests | 14,050 |  | 14,050 |  | 12,750
Total assets | 42,717 |  | 42,717 |  | 33,899
U.S. |  |  |  |  |
OPERATING SEGMENT REPORTING |  |  |  |  |
Exploration costs | 999 | 4,114 | 3,905 | 9,066 |
Operating income (loss) | (4,234) | (5,736) | (7,864) | (11,710) |
Mineral property interests | 229,526 |  | 229,526 |  | 232,704
Total assets | 234,804 |  | 234,804 |  | 238,402
Corporate & Other |  |  |  |  |
OPERATING SEGMENT REPORTING |  |  |  |  |
Exploration costs | 323 | 179 | 897 | 738 |
Operating income (loss) | (2,870) | (3,307) | (11,451) | (6,686) |
Total assets | $ 2,555 |  | $ 2,555 |  | $ 38,054

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