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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Risks and Uncertainties (Details) - USD ($) $ in Millions |  |  |  |  |  | 3 Months Ended
--- | --- | --- | --- | --- | --- | ---
Mar. 29, 2021 | Feb. 09, 2021 | Jan. 29, 2021 | Dec. 31, 2020 | Sep. 10, 2020 | Mar. 31, 2021
Duration of agreement reached to provide additional support to communities and greater long-term certainty for El Gallo project | 10 years |  |  |  |  |
Equity Financing In February 2021 |  |  |  |  |  |
Gross proceeds |  | $ 31.5 |  |  |  |
Canadian Development Expenses | Flow Through Common Shares |  |  |  |  |  |
Gross proceeds |  |  | $ 12.7 |  |  |
Canadian Exploration Expenditures |  |  |  |  |  |
Gross proceeds |  |  |  |  |  | $ 20.2
Canadian Exploration Expenditures | Flow Through Common Shares |  |  |  |  |  |
Gross proceeds |  |  |  | $ 9.8 | $ 10.4 |

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