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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Risks and Uncertainties (Details) - USD ($) $ in Millions |  |  |  | 12 Months Ended
--- | --- | --- | --- | ---
Feb. 09, 2021 | Jan. 29, 2021 | Sep. 10, 2020 | Dec. 31, 2021
Duration current portion of inventories expected to be processed or recovered |  |  |  | 12 months
Duration over which drilling and related costs are capitalized |  |  |  | 1 year
Equity Financing In February 2021 |  |  |  |
Gross proceeds | $ 31.5 |  |  |
Canadian Development Expenses | Equity Financing In February 2021 |  |  |  |
Gross proceeds |  |  |  | $ 31.5
Canadian Development Expenses | Flow Through Common Shares |  |  |  |
Gross proceeds |  | $ 12.7 |  | 12.7
Canadian Development Expenses | Flow Through Common Shares | Los Azules Copper Project |  |  |  |
Gross proceeds |  |  |  | $ 40.0
Canadian Exploration Expenditures | Flow Through Common Shares |  |  |  |
Gross proceeds |  |  | $ 10.4 |

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