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MINERAL PROPERTY INTERESTS AND ASSET RETIREMENT OBLIGATIONS (Tables) | 12 Months Ended
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Dec. 31, 2012
MINERAL PROPERTY INTERESTS AND ASSET RETIREMENT OBLIGATIONS |
Summary of mineral property interests | The values for all of the mineral properties held by the Company as at December 31, 2012 are noted below.
Name of Property/Complex |  | State/Province |  | Country |  | Carrying Value |
--- | --- | --- | --- | --- | --- | --- | ---
Los Azules Copper Project |  | San Juan |  | Argentina |  | $ | 431,190 |
Other San Juan Exploration Properties |  | San Juan |  | Argentina |  | $ | 7,818 |
Telken Tenements |  | Santa Cruz |  | Argentina |  | $ | 40,234 |
Este Tenements |  | Santa Cruz |  | Argentina |  | $ | 8,121 |
Piramides Tenements |  | Santa Cruz |  | Argentina |  | $ | 14,815 |
Tobias Tenements |  | Santa Cruz |  | Argentina |  | $ | 17,719 |
Cerro Mojon Tenements |  | Santa Cruz |  | Argentina |  | $ | 1,971 |
La Merced Tenements |  | Santa Cruz |  | Argentina |  | $ | 1,891 |
Cabeza de Vaca Tenements |  | Santa Cruz |  | Argentina |  | $ | 877 |
El Trumai Tenements |  | Santa Cruz |  | Argentina |  | $ | 1,534 |
Martes 13 Tenements |  | Santa Cruz |  | Argentina |  | $ | 3,568 |
Celestina Tenements |  | Santa Cruz |  | Argentina |  | $ | 1,753 |
Other Santa Cruz Exploration Properties |  | Santa Cruz |  | Argentina |  | $ | 7,601 |
Tonkin Complex |  | Nevada |  | United States |  | $ | 51,989 |
Gold Bar Complex |  | Nevada |  | United States |  | $ | 77,012 |
Limo Complex |  | Nevada |  | United States |  | $ | 50,098 |
North Battle Mountain Complex |  | Nevada |  | United States |  | $ | 4,148 |
East Battle Mountain Complex |  | Nevada |  | United States |  | $ | 4,060 |
West Battle Mountain Complex |  | Nevada |  | United States |  | $ | 8,854 |
Other United States Properties |  | Nevada |  | United States |  | $ | 19,107 |
El Gallo Complex |  | Sinaloa |  | Mexico |  | $ | 8,126 |
Other Mexico Exploration Properties |  | Sinaloa |  | Mexico |  | $ | 4,581 |
Total |  |  |  |  |  | $ | 767,067 |
Schedule of changes in asset retirement obligations | The Company's asset retirement obligations for years ended December 31, 2012 and 2011 are as follows (in thousands):
|  | 2012 |  | 2011 |
--- | --- | --- | --- | --- | ---
Asset retirement obligation liability—opening balance |  | $ | 6,253 |  | $ | 6,153 |
Settlements |  |  | (47 | ) |  | (82 | )
Accretion of liability |  |  | 447 |  |  | 524 |
Adjustment reflecting updated estimates |  |  | (294 | ) |  | (342 | )
Asset retirement obligation liability—ending balance |  | $ | 6,359 |  | $ | 6,253 |

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- Definition Tabular disclosure of the changes in carrying amount of a liability for asset retirement obligations, for changes such as new obligations, changes in estimates of existing obligations, spending on existing obligations, property dispositions, and foreign currency translation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13201-110859 + Details
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