STOCK-BASED COMPENSATION - Compensation Expense (Details) - USD ($)	6 Months Ended	12 Months Ended
	Dec. 31, 2021	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2019
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation expense	$ 2,003,116	$ 1,319,372	$ 470,939	$ 438,375
Exploration and mine development costs
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation expense	687,695	495,031	171,151	85,450
General and administrative expenses
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total stock-based compensation expense	$ 1,315,421	$ 824,341	$ 299,788	$ 352,925