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MINERAL PROPERTY INTEREST AND ASSET RETIREMENT OBLIGATIONS - Mineral Property Interests (Details) - USD ($) $ in Thousands |  |  | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Jun. 30, 2018 | Apr. 19, 2016 | Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2016 | Sep. 30, 2015 | Dec. 31, 2015
Mineral Property Interests |  |  |  |  |  |  |
Purchase price |  |  |  |  | $ 5,950 |  |
Mineral property interests |  |  | $ 242,350 | $ 257,106 | 242,350 | $ 257,106 | $ 237,245
Impairment charges |  |  |  | 1,198 |  | 29,740 |
Recovery of deferred income tax |  |  |  | 10,400 |  | 10,400 |
Income tax recovery |  |  | (607) | (1,619) | (3,330) | (15,103) |
Exploration costs |  |  | (2,166) | (1,830) | $ (5,595) | (7,252) |
Percentage of annual fees on surety bonds |  |  |  |  | 1.50% |  |
Percentage of upfront deposit on surety bonds |  |  |  |  | 10.00% |  |
MSC |  |  |  |  |  |  |
Mineral Property Interests |  |  |  |  |  |  |
Income tax recovery |  |  | (1,691) | (1,630) | $ (7,825) | (6,282) | $ (15,942)
Tonkin Project |  |  |  |  |  |  |
Mineral Property Interests |  |  |  |  |  |  |
Impairment charges |  |  |  |  |  | 8,900 |
Gold Bar Project |  |  |  |  |  |  |
Mineral Property Interests |  |  |  |  |  |  |
Impairment charges |  |  |  |  |  | 20,800 |
Royalty |  |  |  |  |  |  |
Mineral Property Interests |  |  |  |  |  |  |
Required payment of gross revenue less allowable deductions to the tiered net smelter return royalty on the El Gallo 1 Mine (as a percent) |  | 3.50% |  |  |  |  |
Eventually reduced percentage of required payment |  | 1 |  |  |  |  |
Purchase price | $ 1,000 | $ 5,300 |  |  |  |  |
Royalty | Non-current other liabilities |  |  |  |  |  |  |
Mineral Property Interests |  |  |  |  |  |  |
Purchase price |  |  |  |  | 1,000 |  |
Royalty | El Gallo 1 mine |  |  |  |  |  |  |
Mineral Property Interests |  |  |  |  |  |  |
Additional to mineral properties |  | 5,100 |  |  |  |  |
Royalty | El Gallo 2 Properties |  |  |  |  |  |  |
Mineral Property Interests |  |  |  |  |  |  |
Additional to mineral properties |  | $ 1,200 |  |  |  |  |
Argentina |  |  |  |  |  |  |
Mineral Property Interests |  |  |  |  |  |  |
Mineral property interests |  |  | 191,490 | 202,889 | 191,490 | 202,889 |
Exploration costs |  |  | (543) | (268) | (1,046) | (1,190) |
Mexico |  |  |  |  |  |  |
Mineral Property Interests |  |  |  |  |  |  |
Mineral property interests |  |  | 14,062 | 9,730 | 14,062 | 9,730 |
Exploration costs |  |  | $ (1,094) | $ (788) | $ (2,739) | $ (3,662) |

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- Definition The required payment of gross revenue less allowable deductions to the tiered net smelter return royalty (the “Royalty”) on the El Gallo 1 Mine. + References No definition available. + Details
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