Non-current assets - exploration and evaluation (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2026	Dec. 31, 2025
Non-current assets - exploration and evaluation [Abstract]
Exploration assets	$ 214,737	$ 209,009
Reconciliations of written down [Abstract]
Opening balance	209,009	203,110
Additions - Rhyolite Rydge	5,728	5,850
Exploration expenditure - noncore		49
Ending balance	$ 214,737	$ 209,009

The amount of exploration and evaluation assets recognised as tangible assets in accordance with the entity's accounting policy. [Refer: Exploration and evaluation assets [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 6
-IssueDate 2025-01-01
-Paragraph 25
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=6&code=ifrs-tx-2025-en-r&anchor=para_25&doctype=Standard
-URIDate 2025-03-27

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 41
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_41&doctype=Standard
-URIDate 2025-03-27

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Note Effective 2027-01-01
-Name IFRS
-Number 19
-IssueDate 2025-01-01
-Paragraph 41
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=19&code=ifrs-tx-2025-en-r&anchor=para_41&doctype=Standard
-URIDate 2025-03-27

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant