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COMMON SHARES (Details Narrative) - USD ($) $ / shares in Units, $ in Thousands |  |  |  |  |  | 1 Months Ended | 12 Months Ended |  |
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Nov. 13, 2024 | Nov. 05, 2024 | Nov. 04, 2024 | Sep. 17, 2024 | Sep. 02, 2023 | Apr. 21, 2025 | Jan. 31, 2025 | Jun. 30, 2024 | Jun. 24, 2024 | Sep. 30, 2023 | Jun. 30, 2025 | Jun. 30, 2024 | Nov. 30, 2024 | Dec. 31, 2023
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Description of warrants | On November 13, 2024, the Company closed a non-brokered private placement (the “November 2024 Private Offering”), pursuant to binding subscription agreements with certain accredited investors as part of a non-brokered private placement of 2,199,602 units of the Company (the “November 2024 Units”). Each November 2024 Unit consisted of one Common Share, one Warrant (a “Series A Private Warrant”) to purchase one Common Share, and one-half of one Warrant (each whole such Warrant, a “Series B Private Warrant” and, together with the Series A Private Warrants, the “November 2024 Private Warrants”), with each Series B Private Warrant entitling the holder thereof to purchase one additional Common Share. Each November 2024 Unit was issued and sold at a price of $1.57. The gross proceeds of the November 2024 Private Offering were approximately $3,500 before deducting offering expenses. Certain directors and officers of the Company (the “Insider Investors”) purchased November 2024 Units at a price of $1.7675 per November 2024 Unit, which price includes $0.1975 per November 2024 Private Warrant and allowed such directors and officers to participate in the November 2024 Private Offering in accordance with the rules of the Nasdaq. The Series A Private Warrants have an exercise price of $1.75 per underlying Common Share, are exercisable immediately, and will expire on November 13, 2026. The Series B Private Warrants have an exercise price of $2.07 per underlying Common Share, are exercisable beginning six months and one day from the date of issuance and will expire on November 13, 2029. The Company recorded a non-cash expense of $34 and $110 to other operating expenses and employee related costs, respectively, representing the excess of fair value of the November 2024 Units over the purchase price paid by Insider Investors. | On November 5, 2024, the Company closed an underwritten public offering (the “November 2024 Registered Offering”), pursuant to the underwriting agreement, dated November 3, 2024 (the “Underwriting Agreement”), with Maxim Group LLC (“Maxim”), as underwriter, which consisted of 1,592,356 Common Shares, 1,672,090 Warrants (the “Series A Public Warrants”) to purchase up to an additional 1,672,090 Common Shares and 836,045 Warrants (the “Series B Public Warrants” and, together with the Series A Public Warrants, the “November 2024 Public Warrants”) to purchase up to an additional 836,045 Common Shares. Each Common Share was sold together with one Series A Public Warrant and one-half of one Series B Public Warrant at a combined public offering price of $1.57. The gross proceeds from the November 2024 Registered Offering were $2,501 before deducting underwriting discounts and offering expenses. The November 2024 Public Warrants were classified as equity instruments and accordingly, the net proceeds were allocated based on the relative fair values of the Common Shares and the November 2024 Public Warrants on the date of issuance, with $943 allocated to the fair value of the November 2024 Public Warrants and the balance of the proceeds of $1,558 allocated to Common Shares. The Company incurred total transaction costs related to the November 2024 Registered Offering $1,226, which were treated as share issuance costs at closing. The Series A Public Warrants have an exercise price of $1.75 per underlying Common Share, are exercisable immediately, and will expire on November 5, 2026. The Series B Public Warrants have an exercise price of $2.07 per underlying Common Share, are exercisable beginning six months and one day from the date of issuance and will expire on November 5, 2029. In addition, pursuant to the Underwriting Agreement, the Company granted Maxim a 45-day over-allotment option to purchase (i) 238,853 additional Common Shares and (ii) 358,280 Option Warrants (as defined below) to purchase up to an aggregate of 358,280 Common Shares. “Option Warrant” means one Series A Public Warrant combined with one-half of one Series B Public Warrant. On November 4, 2024, Maxim partially exercised its over-allotment option to purchase 79,734 additional Series A Public Warrants and 39,867 additional Series B Public Warrants, which amounts are included in the amounts discussed above and were issued at closing of the November 2024 Registered Offering. |  |  |  |  |  |  |  |  |  |  |  |
Fair value of non operating gain/loss |  |  |  |  |  |  |  |  |  |  | $ 1,928 |  |  |
Registered Offering |  |  |  |  |  |  |  |  |  |  |  |  | $ 161 |
Private Offering |  |  |  |  |  |  |  |  |  |  |  |  | $ 60 |
Common share, description |  |  |  |  |  | On April 21, 2025, the Company closed an underwritten public offering (the “April 2025 Offering”), pursuant to an underwriting agreement, dated April 17, 2025, with Maxim, as underwriter, pursuant to which the Company issued and sold (i) 6,628,846 Common Shares at a public offering price of $2.60 per Common Share and (ii) 1,063,462 pre-funded Warrants (the “April 2025 Pre-Funded Warrants”) to purchase up to an additional 1,063,462 Common Shares at a public offering price of $2.5999. The April 2025 Pre-Funded Warrants have an exercise price of $0.0001 per underlying Common Share, are exercisable immediately, and do not have an expiration date. On April 17, 2025, Maxim partially exercised its over-allotment option to purchase 323,504 additional Common Shares at closing. The gross proceeds from the April 2025 Offering were approximately $20,841 before deducting underwriting discounts and offering expenses. The April 2025 Pre-Funded Warrants were classified as equity instruments and accordingly, the net proceeds were allocated based on the relative fair values of the Common Shares and the April 2025 Pre-Funded Warrants on the date of issuance, with $2,765 allocated to the fair value of the April 2025 Pre-Funded Warrants (based on the value of the underlying Common Shares at closing) and the balance of the proceeds of $18,076 allocated to Common Shares. The Company incurred total transaction costs related to the April 2025 Offering of $2,102, which were treated as share issuance costs at closing. | On January 31, 2025, the Company closed an underwritten registered direct offering (the “January 2025 Offering”), pursuant to an underwriting agreement, dated January 29, 2025, with Maxim, as underwriter, pursuant to which the Company issued and sold 2,577,320 Common Shares, 2,577,320 Series A Warrants to purchase up to 2,577,320 Common Shares (the “January 2025 Series A Warrants”) and 1,288,660 Series B Warrants to purchase up to an additional 1,288,660 Common Shares (the “January 2025 Series B Warrants” and, together with the January 2025 Series A Warrants, the “January 2025 Warrants”). Each Common Share was sold together with one January 2025 Series A Warrant and one-half of one January 2025 Series B Warrant at a combined public offering price of $1.94. The gross proceeds from the January 2025 Offering were approximately $5,000 before deducting underwriting discounts and offering expenses. The January 2025 Warrants were classified as equity instruments, and accordingly, the net proceeds were allocated based on the relative fair values of the Common Shares and the January 2025 Warrants on the date of issuance, with $2,200 allocated to the fair value of the January 2025 Warrants and the balance of the proceeds of $2,800 allocated to Common Shares. The Company incurred total transaction costs related to the January 2025 Offering of $799, which were treated as share issuance costs at closing. The January 2025 Series A Warrants have an exercise price of $1.98 per underlying Common Share, are exercisable immediately, and will expire on August 2, 2027. The January 2025 Series B Warrants have an exercise price of $2.05 per underlying Common Share, are exercisable immediately, and will expire on January 31, 2029. |  |  |  |  |  |  |
Proceeds from equity |  |  |  |  |  |  |  |  |  | $ 962 |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term |  |  |  |  |  |  |  |  |  |  | 5 years | 5 years |  |
Risk-free rate |  |  |  |  |  |  |  |  |  |  | 4.44% | 4.25% |  |
Expected dividend rate |  |  |  |  |  |  |  |  |  |  | 0.00% | 0.00% |  |
Outstanding stock options vested |  |  |  |  |  |  |  |  |  |  | 99.80% |  |  |
Unrecognized compensation costs |  |  |  |  |  |  |  |  |  |  | $ 4 |  |  |
Share based compensation expense |  |  |  |  |  |  |  |  |  |  | $ 789 | $ 2,881 |  |
Exchange of warrants, description |  |  |  |  |  |  |  |  |  |  | NioCorp Assumed Warrant Agreement, through June 30, 2025, a total of 1,165,365 2023 Private Warrants were exchanged for 2023 Public Warrants. Upon exchange, the Company recorded an additional fair value expense of $26 and transferred the fair value of the exchanged 2023 Public Warrants from warrant liabilities to equity. |  |  |
Stock issued, shares |  |  |  | 2,816,742 |  |  |  |  |  |  |  |  |  |
Lind Global Asset Management Three L L C [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contingent consideration description |  |  |  |  |  |  |  |  |  |  | As consideration for entering into the previously publicly disclosed Waiver and Consent Agreement, dated September 25, 2022 (the “Lind Consent”), between the Company and Lind Global Asset Management III, LLC (“Lind III”), Lind III received, amongst other things, the right to receive additional Warrants (the “Contingent Consent Warrants”) if on September 17, 2024, the closing trading price of the Common Shares on the Toronto Stock Exchange or such other stock exchange on which such shares may then be listed, is less than C$10.00, subject to adjustments. The number of Contingent Consent Warrants to be issued, if any, is based on the Canadian dollar equivalent (based on the then current Canadian to U.S. dollar exchange rate as reported by Bloomberg, L.P.) of $5,000 divided by the five-day volume weighted average price of the Common Shares on the date of issuance. Further, the number of Contingent Consent Warrants issued would be proportionately adjusted based on the percentage of Warrants currently held by Lind III that are exercised, if any, prior to the issuance of any Contingent Consent Warrants. |  |  |
G X I I Public Warrants [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Warrants traded prior to the closing |  |  |  |  |  |  |  |  |  |  | 9,999,959 |  |  |
G X I I Private Warrants [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Warrants traded prior to the closing |  |  |  |  |  |  |  |  |  |  | 5,666,667 |  |  |
Lind Consent Warrant Issuance [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common share exercise price, per share |  |  |  | $ 2.308 |  |  |  |  |  |  |  |  |  |
Stock and Warrants Issued During Period, Value, Preferred Stock and Warrants |  |  |  | $ 5,000 |  |  |  |  |  |  |  |  |  |
Yorkville Equity Facility Financing Agreement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net proceeds |  |  |  |  |  |  |  |  |  |  | $ 46,917 |  |  |
Expires date |  |  |  |  |  |  |  |  |  |  | Apr. 01, 2026 |  |  |
Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Remaining proceeds from private warrants |  |  |  |  |  |  |  |  |  |  | $ 1,573 |  |  |
Proceeds from equity |  |  |  |  |  |  |  | $ 441 |  | 708 | 977 |  |  |
Warrant [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from equity |  |  |  |  |  |  |  | $ 161 |  | $ 254 | $ 264 |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term |  |  |  |  |  |  |  |  |  | 2 years | 2 years |  |  |
Risk-free rate |  |  |  |  |  |  |  | 4.73% |  | 4.85% | 4.33% |  |  |
Expected volatility |  |  |  |  |  |  |  | 73.92% |  | 71.63% | 54.80% |  |  |
Expected dividend rate |  |  |  |  |  |  |  | 0.00% |  | 0.00% | 0.00% |  |  |
Public Warrants2023 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Description of warrants |  |  |  |  |  |  |  |  |  |  | (ii) the last reported sale price of the Common Shares equals or exceeds approximately $16.10 per share (as adjusted for stock splits, stock dividends, reorganizations, recapitalizations and the like) for any 20 trading days within a 30-trading day period ending on the third business day prior to the date on which the Company sends the notice of redemption to the Warrant holders |  |  |
Warrant Liability [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gain on issuance of Warrants |  |  |  |  |  |  |  |  |  |  | $ 103 |  |  |
Private Placement [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares issue | 2,199,602 |  |  |  | 250,000 |  |  |  | 315,000 |  | 413,432 |  |  |
Price per unit |  |  |  |  | $ 4.00 |  |  |  | $ 1.91 |  |  |  |  |
Gross proceeds |  |  |  |  | $ 1,000 |  |  |  | $ 602 |  |  |  |  |
Shares price |  |  |  |  | $ 4.60 |  |  |  | $ 2.20 |  |  |  |  | $ 3.54
Other operating expenses |  |  |  |  |  |  |  |  |  |  | $ 92 |  |  |
Employee related costs |  |  |  |  |  |  |  |  |  |  | 10 |  |  |
Private Placement [Member] | Canada, Dollars |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gross proceeds |  |  |  |  |  |  |  |  |  |  | $ 1,290 |  |  |
Private Placement [Member] | Director [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares price |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.205
Units issue and sold |  |  |  |  |  |  |  |  |  |  | 138,845 |  |  |
Private Placement [Member] | Investor [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares price |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 3.08
Units issue and sold |  |  |  |  |  |  |  |  |  |  | 274,587 |  |  |
Purchase Agreement Series A [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument Issued Principalshars |  |  | 79,734 |  |  |  |  |  |  |  |  |  |  |
Purchase Agreement Series B [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Subsidiary, Sale of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument Issued Principalshars |  |  | 39,867 |  |  |  |  |  |  |  |  |  |  |

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