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v3.21.2

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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