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SIGNIFICANT ACCOUNTING POLICIES - Risks and Uncertainties (Details) - USD ($) $ in Millions |  |  |  |  | 6 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | ---
Feb. 09, 2021 | Jan. 29, 2021 | Dec. 31, 2020 | Sep. 10, 2020 | Jun. 30, 2021 | Dec. 31, 2020
Equity Financing In February 2021 |  |  |  |  |  |
Gross proceeds | $ 31.5 |  |  |  | $ 31.5 |
Canadian Development Expenses | Flow Through Common Shares |  |  |  |  |  |
Gross proceeds |  | $ 12.7 |  |  | $ 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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