v3.26.1
Operating segments (Details)
$ in Thousands
 6 Months Ended 12 Months Ended
Dec. 31, 2025
USD ($)
Customer
Jun. 30, 2025
USD ($)
Customer
Jun. 30, 2024
USD ($)
Segment information [Abstract]      
Exploration and evaluation expenditure - non-core $ 0 $ (37)  
Other expenses (1,645) (3,787)  
Reportable segment profit/loss (1,645) (3,824)  
Employee benefits and other expenses (2,721) (6,372)  
Net financing (expense)/income 296 642  
Loss before income tax (4,070) (9,554)  
Segment assets [Abstract]      
Exploration assets 209,009 203,110 $ 187,664
Other assets 23,534 30,431  
Total assets 232,543 233,541  
Segment liabilities [Abstract]      
Payables (1,837) (2,514)  
Provisions (303) (462)  
Total current liabilities (2,140) (2,976)  
Payables (184) (267)  
Total Non-current liabilities (184) (267)  
Net assets $ 230,219 $ 230,298  
Number of major customers | Customer 0 0  
Revenues $ 0 $ 0  
Operating Segments [Member] | North America [Member]      
Segment information [Abstract]      
Exploration and evaluation expenditure - non-core 0 (37)  
Other expenses (741) (1,899)  
Reportable segment profit/loss (741) (1,936)  
Employee benefits and other expenses (964) (2,680)  
Net financing (expense)/income (1,996) (3,173)  
Loss before income tax (3,701) (7,789)  
Segment assets [Abstract]      
Exploration assets 209,009 203,110  
Other assets 12,683 9,443  
Total assets 221,692 212,553  
Segment liabilities [Abstract]      
Payables (1,416) (2,124)  
Provisions (105) (165)  
Total current liabilities (1,521) (2,289)  
Payables (107) (267)  
Total Non-current liabilities (107) (267)  
Net assets 220,064 209,997  
Operating Segments [Member] | Australia [Member]      
Segment information [Abstract]      
Exploration and evaluation expenditure - non-core 0 0  
Other expenses (904) (1,888)  
Reportable segment profit/loss (904) (1,888)  
Employee benefits and other expenses (1,757) (3,692)  
Net financing (expense)/income 2,292 3,815  
Loss before income tax (369) (1,765)  
Segment assets [Abstract]      
Exploration assets 0 0  
Other assets 10,851 20,988  
Total assets 10,851 20,988  
Segment liabilities [Abstract]      
Payables (421) (390)  
Provisions (198) (297)  
Total current liabilities (619) (687)  
Payables (77) 0  
Total Non-current liabilities (77) 0  
Net assets $ 10,155 $ 20,301