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Note 1 - Organization and Business (Details Textual)					1 Months Ended		12 Months Ended		66 Months Ended	69 Months Ended
	Jun. 22, 2021 USD ($)	Dec. 10, 2020 USD ($)	Sep. 30, 2020 USD ($) $ / shares shares	Sep. 29, 2020 USD ($) a	Jun. 30, 2021 USD ($) a $ / shares	Sep. 30, 2020 USD ($) $ / shares shares	Jun. 30, 2021 USD ($) a $ / shares	Jun. 30, 2020 USD ($) $ / shares	Jun. 30, 2020 USD ($) $ / shares	Sep. 29, 2020 USD ($) a	Dec. 31, 2020 USD ($)	Oct. 05, 2020 $ / shares	Oct. 01, 2020	Jan. 08, 2015 USD ($) a
Proceeds from Sale of Equity Method Investments							$ 31,250,000
Common Stock, Par or Stated Value Per Share (in dollars per share) | $ / shares			$ 0.01		$ 0.01	$ 0.01	$ 0.01	$ 0.01	$ 0.01			$ 0.01
Long-term Debt, Total											$ 0
Option Agreement [Member]
Proceeds from Sale of Productive Assets, Total					$ 50,000
Native Village of Tetlin Land [Member]
Percentage of Leasehold Interest														100.00%
Leasehold Interest Acreage (Acre) | a														675,000
Alaska State Mining Claims [Member]
Area of Land (Acre) | a					52,640		52,640
Number of Mining Claims					361		361
The Joint Venture Company [Member] | Separation Agreement [Member]
Net Smelter Returns Silver Royalty, Percent				28.00%						28.00%
The Joint Venture Company [Member] | Option Agreement [Member]
Mining Claims, Option to Acquire, Area (Acre) | a				13,000						13,000
Mining Claims, Option to Acquire, Exercise Price				$ 50,000
The Joint Venture Company [Member] | State of Alaska Mining Claims for Exploration and Development [Member]
Area of Land (Acre) | a					13,000		13,000
Contango Minerals [Member] | Separation Agreement [Member]
Mining Claims Acquired, Area (Acre) | a				167,000
Net Smelter Returns Royalty Interest, Percent				1.00%						1.00%
Contango Minerals [Member] | State of Alaska Mining Claims Located North and Northwest of Tetlin Lease [Member]
Area of Land (Acre) | a					200,000		200,000
Percentage of Mineral Rights					100.00%		100.00%
Royal Alaska and CORE Alaska [Member] | Separation Agreement [Member]
Net Smelter Returns Silver Royalty, Percent				28.00%						28.00%
Tetlin Lease [Member] | The Joint Venture Company [Member]
Area of Land (Acre) | a					675,000		675,000
The Joint Venture Company [Member]
Equity Method Investment, Ownership Percentage			30.00%	30.00%	30.00%	30.00%	30.00%			30.00%	30.00%
Payments to Acquire Interest in Joint Venture									$ 14,300,000
Expected Cash Needed		$ 18,000,000
Exploration Budget Increase (Decrease)	$ 200,000
Proportionate Ownership Share, Approved Budget					$ 5,500,000		$ 5,500,000
Exploration Budget, Funded Amount					$ 2,500,000		$ 2,500,000
Exploration Budget, Total											$ 3,000,000
The Joint Venture Company [Member] | Triple Z [Member]
Prospect Area Ownership Percentage											100.00%
The Joint Venture Company [Member] | KG Mining [Member]
Equity Method Investment, Ownership Percentage by Other Owner			70.00%			70.00%
The Joint Venture Company [Member] | Royal Gold [Member]
Equity Method Investment, Ownership Percentage				40.00%						40.00%
Initial Investment to Fund Exploration Activity														$ 5,000,000
Payments to Acquire Interest in Joint Venture										$ 37,100,000
The Joint Venture Company [Member] | CORE Alaska [Member]
Equity Method Investment, Ownership Percentage			30.00%			30.00%
Proceeds from Sale of Equity Method Investments			$ 32,400,000			$ 32,400,000
Shares Received From Sale of Equity Method Investments (in shares) | shares			809,744			809,744
Sale of Equity Method Investment, Prepayment of Reimbursement			$ 1,200,000			$ 1,200,000
Percentage Ownership in Company													30.00%
The Joint Venture Company [Member] | KG Mining [Member]
Sale of Equity Method Investment, Prepayment of Reimbursement			$ 1,200,000
Percentage Ownership in Company													70.00%
The Joint Venture Company [Member] | Royal Alaska LLC [Member]
Equity Method Investment, Ownership Percentage			40.00%			40.00%
Royal Alaska LLC [Member] | KG Mining [Member]
Percentage Ownership in Company			100.00%			100.00%
Equity Method Investment, Ownership, Shares (in shares) | shares			809,744			809,744
Contango Minerals [Member] | CORE Alaska [Member]
Percentage Ownership in Company				100.00%						100.00%

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