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SHAREHOLDERS' EQUITY (Details) - USD ($) |  |  |  |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Mar. 02, 2022 | Jan. 29, 2021 | Dec. 31, 2020 | Sep. 10, 2020 | Nov. 20, 2019 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Jul. 28, 2022 | Dec. 31, 2019
Price per unit |  |  |  |  |  |  |  |  |  | $ 1 |
Net proceeds |  |  |  |  |  |  | $ 10,320,000 | $ 10,785,000 | $ 15,478,000 |  |
Sale of common stock for cash, net of issuance costs |  |  |  |  |  |  | $ 41,263,000 | $ 29,875,000 |  |  |
Weighted average exercise price of stock options (in dollars per share) |  |  |  |  |  |  |  |  | $ 10.20 |  |
Outstanding options (in shares) |  |  | 701,000 |  |  |  | 447,787 | 616,958 | 701,000 |  | 527,000
Stock options exercised (in shares) |  |  |  |  |  |  |  |  | 14,000 |  |
Stock options issued (in shares) |  |  |  |  |  |  |  | 95,000 | 510,000 |  |
November 2019 Offering |  |  |  |  |  |  |  |  |  |  |
Number of units issued |  |  |  |  | 3,775,000 |  |  |  |  |  |
Price per unit |  |  |  |  | $ 13.25 |  |  |  |  |  |
Net proceeds |  |  |  |  | $ 46,600,000 |  |  |  |  |  |
Warrant expiration term |  |  |  |  | 5 years |  |  |  |  |  |
Issuance costs |  |  |  |  | $ 3,500,000 |  |  |  |  |  |
Outstanding warrants |  |  |  |  |  |  | $ 2,170,625 |  |  |  |
Equity Financing In February 2021 |  |  |  |  |  |  |  |  |  |  |
Number of units issued |  |  |  |  |  |  |  | 3,000,000 |  |  |
Price per unit |  |  |  |  |  |  |  | $ 10.50 |  |  |
Gross proceeds |  |  |  |  |  |  |  | $ 31,500,000 |  |  |
Net proceeds |  |  |  |  |  |  |  | 29,900,000 |  |  |
Issuance costs |  |  |  |  |  |  |  | $ 1,700,000 |  |  |
Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |
Number of units issued |  |  |  |  |  |  | 1,450,000 | 1,260,000 | 1,397,000 |  |
Net proceeds |  |  |  |  |  |  | $ 10,320,000 | $ 10,785,000 | $ 15,478,000 |  |
Shares issued for acquisition of mineral property interests (in shares) |  |  |  |  |  |  |  |  | 5,000 |  |
Stock options exercised (in shares) |  |  |  |  |  |  |  |  | 14,000 |  |
Common Stock [Member] | November 2019 Offering |  |  |  |  |  |  |  |  |  |  |
Net proceeds |  |  |  |  | 37,300,000 |  |  |  |  |  |
Warrant | November 2019 Offering |  |  |  |  |  |  |  |  |  |  |
Net proceeds |  |  |  |  | $ 9,300,000 |  |  |  |  |  |
Number of exercisable warrants to convert to common stock |  |  |  |  | 10 |  |  |  |  |  |
Number of shares of common stock |  |  |  |  | 1 |  |  |  |  |  |
Number of warrants received for each share of common stock share sold |  |  |  |  | 0.50 |  |  |  |  |  |
Warrant at Second Stock Price | November 2019 Offering |  |  |  |  |  |  |  |  |  |  |
Number of shares of common stock |  |  |  |  | 1 |  |  |  |  |  |
Price per common share for each warrant |  |  |  |  | $ 17.22 |  |  |  |  |  |
Flow Through Common Shares | Canadian Development Expenses |  |  |  |  |  |  |  |  |  |  |
Number of units issued |  | 1,260,060 |  |  |  |  |  |  |  |  |
Price per unit |  | $ 10.10 |  |  |  |  |  |  |  |  |
Gross proceeds |  | $ 12,700,000 |  |  |  |  |  |  |  |  |
Net proceeds |  | 12,000,000.0 |  |  |  |  |  |  |  |  |
Issuance costs |  | 700,000 |  |  |  |  |  |  |  |  |
Net proceeds allocated to the sale of tax benefits |  | 1,200,000 |  |  |  |  |  |  |  |  |
Sale of common stock for cash, net of issuance costs |  | $ 10,800,000 |  |  |  |  |  |  |  |  |
Exploration expenditures |  |  |  |  |  |  |  | 12,700,000 |  |  |
Flow Through Common Shares | Canadian Exploration Expenditures |  |  |  |  |  |  |  |  |  |  |
Number of units issued | 1,450,000 |  | 766,990 | 629,816 |  |  |  |  |  |  |
Price per unit | $ 10.40 |  | $ 12.80 | $ 16.50 |  |  |  |  | $ 12.80 |  |
Gross proceeds | $ 15,100,000 |  | $ 9,800,000 | $ 10,400,000 |  |  |  |  |  |  |
Net proceeds | 14,400,000 |  | 9,800,000 | 9,800,000 |  |  |  |  |  |  |
Issuance costs | 800,000 |  | 0 | 600,000 |  |  |  |  |  |  |
Net proceeds allocated to the sale of tax benefits | 4,100,000 |  | 2,100,000 | 2,000,000.0 |  |  |  |  |  |  |
Sale of common stock for cash, net of issuance costs | $ 10,300,000 |  | $ 7,700,000 | $ 7,800,000 |  |  |  |  |  |  |
Exploration expenditures |  |  |  |  |  |  | $ 21,400,000 | $ 12,700,000 |  |  |
Recent Raise |  |  |  |  |  | $15.1 |  |  |  |  |

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