v3.26.1
Basis of presentation and going concern (Narrative) (Details) - USD ($)
$ / shares in Units, $ in Thousands
 1 Months Ended 12 Months Ended
Dec. 04, 2025
Dec. 31, 2025
Dec. 31, 2024
Jun. 24, 2025
Dec. 31, 2023
Disclosure of Basis of Presentation and Going Concern [Line Items]          
Description of share consolidation   2.5 pre-consolidated common shares for one post-consolidated common share      
Cash and cash equivalents   $ 129,783 $ 20,002   $ 2,061
Net loss for the year   (87,446) (49,004)    
Loss on metals contract liability   46,347 10,183    
Net cash used in operating activities   3,945 3,068    
Outstanding current liabilities   86,164 68,590    
Term loan facility   $ 48,230 $ 0    
Senior secured debt facility [Member]          
Disclosure of Basis of Presentation and Going Concern [Line Items]          
Term loan facility       $ 100,000  
Senior secured debt facility [Member] | Initial advance [Member]          
Disclosure of Basis of Presentation and Going Concern [Line Items]          
Term loan facility       50,000  
Senior secured debt facility [Member] | Additional tranches [Member]          
Disclosure of Basis of Presentation and Going Concern [Line Items]          
Term loan facility       $ 25,000  
Crescent Mine [Member]          
Disclosure of Basis of Presentation and Going Concern [Line Items]          
Proceeds from private placement $ 132,300        
Shares issued per share in acquisition $ 4        
Bought deal private placements, shares 11,137,558        
Proceeds from private placement in cash $ 20,000