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SHAREHOLDERS' EQUITY (Details) - USD ($)					3 Months Ended		9 Months Ended		12 Months Ended
	Feb. 09, 2021	Jan. 29, 2021	Dec. 31, 2020	Sep. 10, 2020	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Jun. 30, 2021	Jun. 29, 2021
Common stock, shares authorized										675,000,000	500,000,000
Net proceeds							$ 29,875,000
Sale of common stock for cash, net of issuance costs							29,875,000
November 2019 Offering
Outstanding warrants					$ 21,706,250		21,706,250
March 2019 Offering
Outstanding warrants					8,064,516		8,064,516
Canadian Exploration Expenditures
Gross proceeds									$ 20,200,000
Equity Financing In February 2021
Number of units issued	30,000,000
Price per unit	$ 1.05
Gross proceeds	$ 31,500,000						$ 31,500,000
Net proceeds	29,900,000
Issuance costs	$ 1,700,000
Common Stock [Member]
Number of units issued							30,000,000
Net proceeds							$ 29,875,000
Shares issued for acquisition of mineral property interests (in shares)						53,000		53,000
Flow Through Common Shares | Canadian Development Expenses
Number of units issued		12,600,600
Price per unit		$ 1.01
Gross proceeds		$ 12,700,000					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
Flow Through Common Shares | Canadian Exploration Expenditures
Number of units issued			7,669,900	6,298,166
Price per unit			$ 1.28	$ 1.65					$ 1.28
Gross proceeds			$ 9,800,000	$ 10,400,000
Net proceeds			9,800,000	9,800,000
Issuance costs			0	600,000
Net proceeds allocated to the sale of tax benefits			2,100,000	2,000,000.0
Sale of common stock for cash, net of issuance costs			$ 7,700,000	$ 7,800,000
Exploration expenditures					$ 9,300,000		$ 11,200,000		$ 1,900,000

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Exploration expenses (including prospecting) related to oil and gas producing entities and would be included in operating expenses of that entity. Costs incurred in identifying areas that may warrant examination and in examining specific areas that are considered to have prospects of containing oil and gas reserves, including costs of drilling exploratory wells and exploratory-type stratigraphic test wells. Exploration costs may be incurred both before acquiring the related property (sometimes referred to in part as prospecting costs) and after acquiring the property. Principal types of exploration costs, which include depreciation and applicable operating costs of support equipment and facilities and other costs of exploration activities, are: (i) Costs of topographical, geographical and geophysical studies, rights of access to properties to conduct those studies, and salaries and other expenses of geologists, geophysical crews, and others conducting those studies. Collectively, these are sometimes referred to as geological and geophysical or "G&G" costs. (ii) Costs of carrying and retaining undeveloped properties, such as delay rentals, ad valorem taxes on properties, legal costs for title defense, and the maintenance of land and lease records. (iii) Dry hole contributions and bottom hole contributions. (iv) Costs of drilling and equipping exploratory wells. (v) Costs of drilling exploratory-type stratigraphic test wells.

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