Fair value measurement - Copper stream embedded derivative, continuity schedule (Details) - Copper stream embedded derivative - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024
Continuity schedule for embedded derivative
Balance as of beginning of period	$ 5,182	$ (773)
Initial recognition		0
Change in fair value	2,899	8,946
Balance as of end of period	$ 8,081	$ 8,173

The amount of financial assets classified as derivative instruments. [Refer: Financial assets; Derivatives [member]]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
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- Definition

The gains (losses) including exchange differences recognised in profit or loss on the fair value measurement of assets. [Refer: At fair value [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 13
-IssueDate 2024-01-01
-Paragraph 93
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- Definition

The increase in the fair value measurement of assets resulting from issues of those assets. [Refer: At fair value [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 13
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- References

No definition available.

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