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CONVERTIBLE DEBT (Details Narrative) - USD ($) $ / shares in Units, $ in Thousands |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jul. 19, 2024 | Apr. 30, 2024 | Jun. 30, 2025
Short-Term Debt [Line Items] |  |  |
Transaction loss |  |  | $ 482
Fair Value, Recurring [Member] |  |  |
Short-Term Debt [Line Items] |  |  |
Transaction loss |  | $ 474 |
Fair value |  | 10,315 |
Transaction loss |  | $ 4,256 |
Yorkville Convertible Debt Financing Agreement [Member] |  |  |
Short-Term Debt [Line Items] |  |  |
Principal and accrued interest | $ 95 |  |
Principal and accrued interest |  |  | $ 19
Yorkville Convertible Debt Financing Agreement [Member] | Warrant [Member] |  |  |
Short-Term Debt [Line Items] |  |  |
Number of shares purchase |  |  | 1,789,267
Number of shares purchase |  |  | $ 8.9422
Unsecured Debt [Member] |  |  |
Short-Term Debt [Line Items] |  |  |
Principal and accrued interest | $ 554 |  |
Unsecured Debt [Member] | Yorkville Convertible Debt Financing Agreement [Member] |  |  |
Short-Term Debt [Line Items] |  |  |
Aggregate principal amount |  |  | $ 16,000
Yorkville Convertible Debentures [Member] |  |  |
Short-Term Debt [Line Items] |  |  |
Convertible debt, description |  |  | Pursuant to the Yorkville Convertible Debt Financing Agreement, at the Closing, Yorkville advanced a total amount of $15,360 to NioCorp in consideration of the issuance by NioCorp to Yorkville of (i) $16,000 aggregate principal amount of unsecured convertible debentures (the “Convertible Debentures”) and (ii) Warrants exercisable for up to 1,789,267 Common Shares for cash or, if at any time there is no effective registration statement registering, or no current prospectus available for, the resale of the underlying Common Shares, on a cashless basis, at the option of the holder, at a price per Common Share of approximately $8.9422, subject to adjustment to give effect to any stock dividend, stock split, reverse stock split or similar transaction.

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