MAC COPPER LTD, 6-K filed on 8/25/2025
Report of Foreign Issuer
v3.25.2
Document and Entity Information
 6 Months Ended
Jun. 30, 2025
Document and Entity Information [Abstract]  
Document Type 6-K
Document Period End Date Jun. 30, 2025
Entity Registrant Name MAC Copper Ltd
Current Fiscal Year End Date --12-31
Document Fiscal Year Focus 2025
Document Fiscal Period Focus Q2
Entity Central Index Key 0001950246
Amendment Flag false
v3.25.2
Condensed consolidated statement of comprehensive income - USD ($)
$ in Thousands
 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Condensed consolidated statement of comprehensive income    
Revenue $ 163,228 $ 182,160
Cost of goods sold (101,581) (118,158)
Administrative expenses (20,820) (12,222)
Selling and distribution expenses (10,218) (6,080)
Other (expenses)/income, net (681) 319
Income from operations 29,928 46,019
Finance income 3,187 1,652
Finance costs (55,017) (33,451)
Net change in fair value of financial instruments (57,298) (109,323)
Net finance costs (109,128) (141,122)
Loss before income taxes (79,200) (95,103)
Income tax benefit/(expense) 2,514 (7,066)
Net loss for the period (76,686) (102,169)
Total comprehensive loss for the period $ (76,686) $ (102,169)
Basic loss per ordinary share $ (0.93) $ (1.56)
Diluted loss per ordinary share $ (0.93) $ (1.56)
v3.25.2
Condensed consolidated statement of financial position - USD ($)
$ in Thousands
Jun. 30, 2025
Dec. 31, 2024
Current assets    
Cash and cash equivalents $ 102,109 $ 171,897
Trade and other receivables 14,904 7,310
Inventories 34,532 27,979
Investments 5,538  
Prepayments and other current assets 362 757
Total current assets 157,445 207,943
Non-current assets    
Property, plant and equipment 1,164,712 1,171,049
Exploration and evaluation 27,486 24,388
Inventories 185 222
Investments   3,984
Total non-current assets 1,192,383 1,199,643
Total assets 1,349,828 1,407,586
Current liabilities    
Trade and other payables 79,742 51,050
Lease liability 5,872 4,484
Loans and borrowings 42,255 58,266
Derivative financial liabilities 25,722 22,179
Current tax liability 12,310 7,314
Provisions 12,413 13,357
Other financial liabilities 92,060 29,485
Total current liabilities 270,374 186,135
Non-current liabilities    
Lease liability 1,572 5,749
Loans and borrowings 325,321 344,925
Derivative financial liabilities 50,014 57,065
Deferred tax liability 111,976 119,487
Provisions 21,594 20,547
Liability for cash-settled share-based payments 14,904 5,631
Other financial liabilities 74,270 112,554
Total non-current liabilities 599,651 665,958
Total liabilities 870,025 852,093
Net assets 479,803 555,493
Equity    
Share capital 8 8
Share premium 802,441 801,445
Other capital reserves 1,212 1,212
Accumulated deficit (323,858) (247,172)
Total equity $ 479,803 $ 555,493
v3.25.2
Condensed consolidated statement of changes in equity - USD ($)
$ in Thousands
Share capital
Share premium
DSU
Share premium
RSU
Share premium
Other capital reserves
Accumulated deficit
DSU
RSU
Total
Balance as of beginning at Dec. 31, 2023 $ 5     $ 432,295 $ 1,212 $ (165,485)     $ 268,027
ASX capital raise 2     211,708         211,710
Share issuance cost       (6,912)         (6,912)
Shares issued on redemption of warrants       65,854         65,854
Shares issued on redemption   $ 246         $ 246    
Net loss (in US$)           (102,169)     (102,169)
Balance as of ending at Jun. 30, 2024 7     703,192 1,212 (267,654)     436,757
Balance as of beginning at Dec. 31, 2024 8     801,445 1,212 (247,172)     555,493
Shares issued on redemption     $ 996         $ 996  
Net loss (in US$)           (76,686)     (76,686)
Balance as of ending at Jun. 30, 2025 $ 8     $ 802,441 $ 1,212 $ (323,858)     $ 479,803
v3.25.2
Condensed consolidated statement of cash flows - USD ($)
$ in Thousands
 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Cash flows from operating activities:    
Loss before income taxes $ (79,200) $ (95,103)
Adjustments to reconcile net loss to net cash used in operating activities:    
Depreciation and amortisation 37,882 38,365
Net foreign exchange losses/(gains) 575 (886)
Finance income (3,187) (766)
Finance costs 54,442 33,451
Net change in fair value measurements of financial assets and liabilities 57,298 109,323
Movement in provisions (1,438) (2,187)
Other non-cash transactions   (2,099)
Changes in operating assets and liabilities:    
(Increase)/decrease in trade receivables (7,047) 24,524
(Increase)/decrease in other receivables (487) 336
Decrease in prepayments 354 529
Increase in inventories (6,516) (1,048)
Increase/(decrease) in trade payables 7,140 (388)
Increase/(decrease) in other payables 19,004 (9,622)
Decrease in derivative financial instruments (6,848) (11,593)
Increase in liability for cash-settled share-based payments 10,315 4,627
Decrease in deferred liabilities (25) (3,057)
Cash used in operating activities 82,262 84,406
Interest received 1,620 766
Interest paid (18,429) (30,067)
Net cash from operating activities 65,453 55,105
Cash flows from investing activities:    
Purchase of property, plant, and equipment and intangibles (33,206) (24,113)
Exploration and evaluation (3,098) (3,308)
Investment in equity instruments (1,582) (1,846)
Proceeds from sale of investment in equity instruments 2,597  
Acquisition of subsidiary   (75,000)
Payment of contingent royalty consideration (2,425) (1,815)
Stamp duty paid on acquisition of subsidiary   (23,213)
Net cash used in investing activities (37,714) (129,295)
Cash flows from financing activities:    
Proceeds from issue of share capital   204,796
Payment of deferred underwriting and transaction costs   (12,968)
Proceeds from loans and borrowings 62,725  
Repayment of loans and borrowings (145,339) (45,441)
Repayment of silver and copper stream loans (11,549)  
Repayment of working capital loan   (11,522)
Payment of lease liabilities (3,779) (4,002)
Net cash from financing activities (97,942) 130,863
Net change in cash (70,203) 56,673
Cash, beginning of the period 171,897 32,372
Net foreign exchange difference 415 (307)
Cash, end of the period $ 102,109 $ 88,738
v3.25.2
Corporate information
 6 Months Ended
Jun. 30, 2025
Corporate information  
Corporate information

1.Corporate information

MAC Copper Limited (“MAC”, the “Company” or “we”), is a Company incorporated under the laws of Jersey, with limited liability. MAC was incorporated on 29 July 2022 with registered address 3rd Floor, 44 Esplanade St. Helier, JE4 9WG, Jersey. The Company and its subsidiaries (collectively referred herein as the “Group”) are primarily engaged in the operation of the Cornish, Scottish and Australian underground copper mine (the “CSA mine”) in Australia, owned by Cobar Management Pty Limited (“CMPL”), one of the wholly owned subsidiaries of the Company. The principal place of business of the Company is 3rd Floor, 44 Esplanade St. Helier, JE4 9WG, Jersey.

On 27 May 2025, MAC announced that it has entered into a binding scheme implementation deed with Harmony Gold Mining Company Limited (“Harmony”) and Harmony Gold (Australia) Pty Ltd (“Harmony Australia”), a wholly owned subsidiary of Harmony, under which it is proposed that Harmony Australia will acquire 100% of the issued share capital in MAC by way of a Jersey scheme of arrangements (the “Scheme”) and MAC shareholders will receive US$12.25 cash (the “Scheme Consideration”) per MAC share (the “Transaction” or the “Harmony Transaction”).

As at 30 June 2025, the Scheme remained subject to certain conditions including restructuring and amendment or restatement of MAC’s streaming and royalty arrangements, shareholders vote and regulatory approvals. Note 20 provides a summary of the progress on the Harmany transaction subsequent to the period end.
v3.25.2
Basis of accounting
 6 Months Ended
Jun. 30, 2025
Basis of accounting  
Basis of accounting

2.Basis of accounting

(a)Statement of compliance

These condensed consolidated interim financial statements (“interim financial statements”) of the Group are general purpose financial statements prepared in accordance with IAS 34 Interim Financial Reporting.

These interim financial statements do not include all of the information required for a complete set of annual financial statements and should be read in conjunction with the annual financial statements of the Group for the year ended 31 December 2024. However, selected explanatory notes are included to explain events and transactions that are significant to an understanding of the changes in the Group’s financial position and performance since the last annual consolidated financial statements as at and for the year ended 31 December 2024.

These interim financial statements reflect all adjustments, which consist of normal and recurring adjustments necessary to present fairly the financial position as at 30 June 2025 and the results of operations and cash flows for the six months ended 30 June 2025 (“interim reporting period”). Operating results for the six months ended 30 June 2025 are not necessarily indicative of the results that may be expected for the full year ending 31 December 2025.

(b)Basis of measurement

These interim financial statements have been prepared on an accruals basis and are based on historical cost except for certain financial assets and liabilities which are measured at fair value. Historical cost is generally based on the fair values of the consideration given in exchange for assets.

All values in these interim financial statements are rounded to the nearest thousand, except where otherwise indicated.

(c)Functional and presentation currency

These interim financial statements are presented in U.S. dollars (“USD”, “US$” or “$”), which is the Group’s functional currency.

(d)Going concern

These interim financial statements have been prepared on a going concern basis, which contemplates the continuity of normal business activities and the realisation of assets and the settlement of liabilities in the ordinary course of business.

2.Basis of accounting (continued)

(d)Going concern (continued)

As at 30 June 2025, the Group’s current liabilities exceed current assets by $112,929 thousand (31 December 2024: current assets exceeded current liabilities by $21,808 thousand).

In the event of the Scheme being implemented (refer Note 1 above), MAC and all its assets and liabilities will transfer to Harmony Australia and Harmony will be responsible to meet MAC’s obligations as and when they fall due.

As the implementation of the Scheme remains subject to certain conditions outside the control of both parties, to support the assessment of going concern, management have prepared a cashflow forecast which is independent of the Harmony Transaction and covers the period of at least 12 months from the date of these interim financial statements. Based on the cashflow forecast, management anticipates that the Group will be able to pay its debts as and when they fall due during this period. Noting the inherent risks associated with achieving the cashflow forecast, key assumptions in the cashflow forecast include:

●The CSA mine achieving copper production within the guidance range announced by the Company;
●The Group continuing to maintain the efficiencies achieved within the CSA mine;
●The CSA mine producing sufficient cash inflows to fund MAC’s financing arrangements; and
●Continued strong copper price environment.

The Directors have a reasonable expectation that these assumptions can be satisfied and believe it is appropriate to prepare these interim financial statements on a going concern basis. In the event that the key assumptions noted above are not achieved and additional funding is required, the Group can seek alternative sources of funding which the Directors believe would be available including the draw down of the revolving facility.

v3.25.2
Changes in accounting standards and the Group's accounting policies
 6 Months Ended
Jun. 30, 2025
Changes in accounting standards and the Group's accounting policies  
Changes in accounting standards and the Group's accounting policies

3.Changes in accounting standards and the Group’s accounting policies

The accounting policies applied in these interim financial statements are consistent with those applied in the Group’s full year consolidated financial statements. The Group has not early adopted any standard, interpretation or amendment that has been issued but is not yet effective. Several amendments apply for the first time in 2025, but do not have a material impact on the interim financial statements of the Group.

v3.25.2
Use of judgements and estimates
 6 Months Ended
Jun. 30, 2025
Use of judgements and estimates  
Use of judgements and estimates

4.Use of judgements and estimates

In preparing these interim financial statements, management has made judgements and estimates that affect the application of the Group’s accounting policies and the reported amounts of assets, liabilities, income and expenses. Actual results may differ from these estimates.

The significant judgements made by management in applying the Group’s accounting policies and the key sources of estimation uncertainty were the same as those described in the full year consolidated financial statements.

Estimates and underlying assumptions are reviewed on an ongoing basis and are consistent with the Group’s risk management commitments, where appropriate. Revisions to estimates are recognised prospectively.

Measurement of fair values

A number of the Group’s accounting policies require the measurement of fair values, for both financial assets and liabilities and non-financial assets and liabilities.

4.Use of judgements and estimates (continued)

Measurement of fair values (continued)

Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date, regardless of whether that price is directly observable or estimated using another valuation technique. In estimating the fair value of an asset or a liability, the Group takes into account the characteristics of the asset or liability if market participants would take those characteristics into account when pricing the asset or liability at the measurement date. Fair value for measurement and/or disclosure purposes in these interim financial statements is determined on such a basis, except for leasing transactions that are within the scope of IFRS 16 Leases (“IFRS 16”), and measurements that have some similarities to fair value but are not fair value, such as net realisable value in IAS 2 Inventories (“IAS 2”) or value in use in IAS 36 Impairment of Assets (“IAS 36”).

In addition, for financial reporting purposes, fair value measurements are categorised into Level 1, 2 or 3 based on the degree to which the inputs to the fair value measurements are observable and the significance of the inputs to the fair value measurement in its entirety, which are described as follows:

●Level 1 inputs are quoted prices (unadjusted) in active markets for identical assets or liabilities that the entity can access at the measurement date;
●Level 2 inputs are inputs, other than quoted prices included within Level 1, that are observable for the asset or liability, either directly or indirectly; and
●Level 3 inputs are unobservable inputs for the asset or liability.

Further information about the assumptions made in measuring fair values is included in Note 15.
v3.25.2
Segment information
 6 Months Ended
Jun. 30, 2025
Segment information  
Segment information

5.Segment information

The chief operating decision maker has been identified as the Chief Executive Officer (“CEO”). The CEO makes decisions with respect to allocation of resources and assesses performance of the Group. The Group is organised and operates in one single operating segment focused on the mining and production of copper and silver from the CSA mine. As such the performance of the Group is assessed and managed in totality.

The CEO primarily uses a non-IFRS measure of adjusted earnings before interest, tax, depreciation and amortisation (see Adjusted EBITDA below) to assess the performance of the Group. The CEO also receives information about the Group’s revenue on a monthly basis. Information about the Group’s revenue is disclosed in Note 6.

​

Adjusted EBITDA

Adjusted EBITDA excludes the effects of significant items of income and expenditure which might have an impact on the quality of earnings such as restructuring costs, legal expenses and impairments where the impairment is the result of an isolated, non-recurring event. It also excludes the effects of equity-settled share-based payments and unrealised gains or losses on financial instruments.

5.Segment information (continued)

Adjusted EBITDA (continued)

Adjusted EBITDA reconciles to loss after tax as follows:

​

​

​

​

​

​

​

​

Six months ended 30 June

US$thousand

    

2025

    

2024

​

​

​

​

​

Loss after tax

 

(76,686)

 

(102,169)

Income tax (benefit)/expense

 

(2,514)

 

7,066

Net finance costs

 

51,830

 

31,799

Net change in fair value of financial instruments

 

57,298

 

109,323

Operating profit

 

29,928

 

46,019

Depreciation and amortisation

 

37,882

 

38,365

Organisational restructuring expenses

 

—

 

988

IPO and transaction costs1

 

2,717

 

2,615

Other significant expenses2

 

10,693

 

2,582

Adjusted EBITDA

 

81,220

 

90,569

1 related to the ASX IPO, acquisition of the CSA Copper Mine, refinancing and other investment decisions

2 includes discretionary bonuses and share based payments that would be due if the Scheme is implemented
v3.25.2
Revenue
 6 Months Ended
Jun. 30, 2025
Revenue  
Revenue

6.Revenue

​

​

​

​

​

​

​

​

Six months ended 30 June

US$ thousand

    

2025

    

2024

Sale of commodities - Copper

 

156,456

 

176,270

Sale of commodities - Silver

 

6,772

 

5,890

Total

 

163,228

 

182,160

​

Upon the acquisition of CMPL, the Company entered into an Offtake Agreement with Glencore International AG (“GIAG”), the Switzerland-based parent entity of Glencore Operations Australia Pty Limited (“Glencore”). The Offtake Agreement is a LOM obligation, pursuant to which the Company is committed to selling all the material to Glencore, and GIAG is committed to buying all the material.

Revenue is derived principally from the sale of commodities, recognised once the control of the goods has transferred from the Group to the customer.

Products of the Group may be provisionally priced at the date revenue is recognised. As at 30 June 2025, the Group had 11,826.73 payable copper metal tonnes of provisionally priced copper sales subject to final pricing over the next several months (31 December 2024: 9,949.32 payable copper metal tonnes). The average provisional price per tonne of these provisionally priced sales subject to final pricing is $9,551.84 (31 December 2024: $9,140.24). Impact of provisionally priced sales is accounted under IFRS 9 Financial Instruments (“IFRS 9”). Final settlements are recognised within revenue.

Under the Group’s sales offtake agreement, optionality exists to allow the parties to the transaction to complete advance payment sales. In such cases, the product may be sold at either the mine site and/or at port with title and control transferring earlier in the process than otherwise. For two transactions that occurred during the 2024 comparative period, the Group had applied ‘bill and hold’ guidance under IFRS 15. In applying this guidance, the key judgment in determining when to recognise revenue is assessing whether the bill and hold arrangement has substance. In assessing the substance of the bill and hold arrangement, the Group had considered the fact pattern specific to the sales in question, delays that occurred beyond both parties’ control, the structure of the contract with the counterparty, and the reason for the execution of the sale.
v3.25.2
Finance income and costs
 6 Months Ended
Jun. 30, 2025
Finance income and costs  
Finance income and costs

7.Finance income and costs

​

​

​

​

​

​

​

​

Six months ended 30 June

US$ thousand

    

2025

    

2024

Finance income

 

  

 

  

Interest income

 

1,639

 

766

Realised gain on sale of investments

 

1,548

 

—

Foreign exchange gain

​

—

​

886

Total finance income

 

3,187

 

1,652

​

​

​

​

​

Finance costs

 

  

 

  

Interest expense under the effective interest rate method on:

 

  

 

  

– Loans and borrowings

 

(33,176)

 

(26,303)

– Lease liabilities

 

(446)

 

(725)

Debt extinguishment and modification costs

​

(12,469)

​

—

Unwinding of discount on rehabilitation provision

​

(412)

​

(532)

Commodity swap loss

​

(7,794)

​

(5,714)

Realised loss on warrants redemption

​

—

​

(148)

Realised loss on copper and silver streams

​

(145)

​

(29)

Foreign exchange loss

 

(575)

 

—

Total finance costs

 

(55,017)

 

(33,451)

​

​

​

​

​

Net change in fair value measurements of financial instruments

 

  

 

  

Change in fair value of:

 

  

 

  

– Warrant liability

 

(3,769)

 

(40,845)

– Equity instruments

​

750

​

(495)

– Embedded derivative – copper and silver streams

 

(20,848)

 

(27,598)

– Embedded derivative – mezzanine debt facility

 

—

 

185

– Contingent liability – royalty deed

​

(1,304)

​

(7,213)

– Contingent liability – copper consideration

​

(25,540)

​

(10,200)

– Commodity swap liability

​

(6,587)

​

(23,157)

Total net change in fair value of financial instruments

 

(57,298)

 

(109,323)

​

​

​

​

​

Net finance costs

 

(109,128)

 

(141,122)

​
v3.25.2
Income Taxes
 6 Months Ended
Jun. 30, 2025
Income taxes  
Income taxes

8.Income taxes

The Group calculates the period income tax expense using the tax rate that would be applicable to the expected total annual earnings. The major components of income tax expense in the condensed consolidated statement of comprehensive income are:

​

​

​

​

​

​

​

​

Six months ended 30 June

US$ thousand

    

2025

    

2024

Current income tax expense

 

4,996

 

3,521

​

 

4,996

 

3,521

​

​

​

​

​

Deferred tax (benefit)/expense

 

​

 

​

Origination and reversal of temporary differences

 

(7,510)

 

3,545

​

 

(7,510)

 

3,545

Total income tax (benefit)/expense

 

(2,514)

 

7,066

​
v3.25.2
Inventories
 6 Months Ended
Jun. 30, 2025
Inventories  
Inventories

9.Inventories

​

​

​

​

​

​

​

    

30 June

    

31 December

US$ thousand

​

2025

    

2024

Current

 

  

 

  

Supplies and consumables

 

13,545

 

11,601

Work in progress

 

2,782

 

1,890

Finished goods

 

18,205

 

14,488

Total current

 

34,532

 

27,979

​

​

​

​

​

Non-current

 

  

 

  

Supplies and consumables

 

185

 

222

Total non-current

 

185

 

222

Total inventories

 

34,717

 

28,201

​

At 30 June 2025:

●Work in progress and finished goods inventory is measured at cost with no inventory write-downs (31 December 2024: $nil).
●Supplies and consumables is measured at cost less allowance for obsolete stock of $700 thousand (31 December 2024: $700 thousand).
●Inventories that are not expected to be utilised or sold within 12 months are classified as non-current inventory and held in Australia.
v3.25.2
Property, plant and equipment
 6 Months Ended
Jun. 30, 2025
Property, plant and equipment  
Property, plant and equipment

10.Property, plant and equipment

(a)Acquisitions and disposals

During the six months ended 30 June 2025, the Group acquired assets with a cost of $32,759 thousand (30 June 2024: $28,723 thousand). This includes costs incurred for mine development amounting to $14,022 thousand (30 June 2024: $11,318 thousand) and additions to assets under construction amounting to of $18,706 thousand of $18,706 thousand (30 June 2024: $17,149 thousand).

(b)Depreciation

During the six months ended 30 June 2025, the Group recognised $37,882 thousand (30 June 2024: $34,096 thousand) of depreciation expense in cost of goods sold.
v3.25.2
Loans and borrowings
 6 Months Ended
Jun. 30, 2025
Loans and borrowings  
Loans and borrowings

11.Loans and borrowings

​

​

​

​

​

​

​

    

30 June

    

31 December

US$ thousand

​

2025

    

2024

Current

 

  

 

  

Senior syndicated facility

 

21,328

 

38,644

Copper stream

 

10,726

 

10,275

Silver stream

 

10,201

 

9,347

​

 

42,255

 

58,266

​

​

​

​

​

Non-current

 

  

 

  

Mezzanine debt facility

 

—

 

95,003

Senior syndicated facility

 

194,492

 

116,032

Copper stream

 

75,250

 

75,636

Silver stream

 

55,579

 

58,254

​

 

325,321

 

344,925

​

 

367,576

 

403,191

​

The following table presents the continuity schedule of loans and borrowings during the period ended 30 June 2025:

​

​

​

​

US$ thousand

​

Carrying amount

Balance as of 1 January 2025

 

403,191

Drawdowns

 

​

Drawdown of senior syndicated facility

 

66,000

Arrangement fee deducted from drawdown

 

(3,275)

​

​

​

Repayments

 

​

Mezzanine debt facility

 

(112,984)

Copper and silver delivered against copper and silver stream

 

(11,549)

​

​

​

Other movements

 

​

Debt extinguishment and modification costs

 

12,469

Amortisation expense

 

13,724

Balance as of 30 June 2025

​

367,576

​

During the period, on 13 March 2025, MAC announced the amendments to the Company’s debt structure. As a result of these amendments:

​

a)

the senior syndicated facility agreement (“SFA”) has been amended in the following manner:

●National Australia Bank Limited, Westpac Banking Corporation and Macquarie Bank Limited have joined the group of Senior Lenders;
●Repayments under Facility A of $159,000 thousand have been deferred until 30 September 2025;
●Revolving Facility B has been increased from $25,000 thousand to $125,000 thousand;
●A new letter of credit facility (“Facility C”) of $45,000 thousand has been added to the SFA, which has been utilised to replace Glencore’s performance guarantee in relation to the rehabilitation costs associated with CMPL mining activities (refer Note 19);
●Final scheduled maturity date of these facilities has been extended to 14 March 2028; and

11.Loans and borrowings (continued)

●Margin included in the interest on these facilities has been changed from a fixed 3.0% per annum to a range of 2.50% to 3.0% depending on MAC’s Net Debt to EBITDA ratio defined in the amended SFA.

b)

MAC exercised its right to repay the mezzanine debt facility in full. MAC utilised the proceeds from the 15 October 2024 private placement and $66,000 thousand drawdown from Facility B of the SFA to pay off a total of $160,656 thousand to Sprott Private Resource Lending II (Collector-2), LP, including the prepayment interest premium, as full and final settlement of the Mezzanine debt facility, excluding Mezz Warrants as summarised below:

​

​

​

​

​

    

Six months ended

US$ thousand

​

30 June 2025

Repayment - Mezzanine debt facility

​

112,984

Repayment - Mezzanine debt facility embedded derivative (Note 15)

​

32,355

Total repayment before interest and costs

​

145,339

​

​

​

Accrued interest up to the date of repayment

​

3,652

Additional prepayment interest per the terms of early settlement

​

10,597

Other costs related to settlement

​

1,068

Total repayment

​

160,656

​
v3.25.2
Provisions
 6 Months Ended
Jun. 30, 2025
Provisions  
Provisions

12.Provisions

​

​

​

​

​

​

​

​

​

    

Employee

    

Rehabilitation

    

​

US$ thousand

    

entitlements

    

costs

    

Total

Balance as of 1 January 2025

 

14,606

 

19,298

 

33,904

Released

​

(1,395)

​

—

​

(1,395)

Additions

​

—

​

622

​

622

Accretion

​

—

​

412

​

412

Movements from foreign exchange impact

​

464

​

—

​

464

Balance as of 30 June 2025

​

13,675

​

20,332

​

34,007

​

​

​

​

​

​

​

Current

​

12,413

​

—

​

12,413

Non-current

​

1,262

​

20,332

​

21,594

Balance as of 30 June 2025

​

13,675

​

20,332

​

34,007

​
v3.25.2
Other financial liabilities
 6 Months Ended
Jun. 30, 2025
Other financial liabilities.  
Other financial liabilities

13.Other financial liabilities

​

​

​

​

​

​

​

    

30 June

    

31 December

US$ thousand

​

2025

    

2024

Current

 

  

 

  

Contingent consideration

 

86,050

 

23,680

Royalty liability

​

5,785

​

5,592

Financial liabilities arising from sale and leaseback transaction

 

225

 

213

​

​

92,060

​

29,485

​

 

​

 

​

Non-current

​

​

​

​

Contingent consideration

 

33,540

 

70,370

Royalty liability

​

40,730

​

42,069

Financial liabilities arising from sale and leaseback transaction

 

—

 

115

​

 

74,270

 

112,554

​

​

166,330

​

142,039

​
v3.25.2
Financial instruments and financial risk management
 6 Months Ended
Jun. 30, 2025
Financial instruments and financial risk management  
Financial instruments and financial risk management

14.Financial instruments and financial risk management

Due to the nature of operations, the Group is subject to certain financial risks. The key financial risk factors that arise from the Group’s activities, including the Group’s policies for managing the financial risks, are outlined below.

(a)Market risk

Commodity price risk

The Group is subject to price risk associated with fluctuations in the market prices for copper and silver. A significant change in commodity prices could have a material effect on the Group’s revenues and financial instruments, including certain derivative instruments and contingent consideration whose values fluctuate with changes in the prices of copper or silver (Note 15).

The Group closely monitors trends in the market prices of copper, silver and other metals as part of its routine activities, as these trends could significantly impact future cash flows. As at 30 June 2025, the Group estimates that a 10% increase (decrease) in price of commodities sold with provisional pricing feature, with all other variables held constant, would result in an increase (decrease) of $11,297 thousand (31 December 2024: $9,094 thousand) in profit after tax. Also refer Note 15 for a description of how the changes in commodity price may affect certain derivative instruments and contingent consideration.

Currency risk

The foreign currency transactions entered into by the Group are not generally hedged. The carrying amounts of the Group’s foreign currency denominated monetary assets and liabilities are as follows:

​

​

​

​

​

​

​

​

​

    

Australian

    

​

    

​

Local currency thousand

​

Dollar

​

Euro

​

Total

30 June 2025

 

  

 

  

 

  

Cash and cash equivalents

 

37,550

 

—

 

37,550

Trade and other receivables

 

1,806

 

—

 

1,806

Trade and other payables

 

(57,315)

 

—

 

(57,315)

Lease liabilities

 

(11,365)

 

—

 

(11,365)

Total

 

(29,324)

 

—

 

(29,324)

​

 

​

 

​

 

​

31 December 2024

​

​

​

​

​

​

Cash and cash equivalents

​

76,497

​

—

​

76,497

Trade and other receivables

​

661

​

—

​

661

Trade and other payables

​

(48,024)

​

(25)

​

(48,049)

Lease liabilities

​

(16,460)

​

—

​

(16,460)

Total

​

12,674

​

(25)

​

12,649

​

The following table details the Group’s estimated sensitivity to a 10% increase (decrease) in the USD against the relevant foreign currencies as a result of translating the Group’s foreign currency denominated monetary assets and liabilities.

A positive number below indicates an increase in profit where the USD strengthens 10% against the relevant currency. For a 10% weakening of the USD against the relevant currency, there would be a comparable impact on the profit and the balances below would be negative.

​

​

​

​

​

​

​

​

30 June

​

31 December

US$ thousand

​

2025

    

2024

Australian Dollar

 

  

 

  

Profit or loss

 

(1,921)

 

788

​

​

​

​

​

Other

 

  

 

  

Profit or loss

 

—

 

(2)

​

14.Financial instruments and financial risk management (continued)

(a)Market risk (continued)

Interest rate risk

As at 30 June 2025, the Group estimates that a 1% increase (decrease) in interest rates, with all other variables held constant, would result in an increase (decrease) of $563 thousand (31 December 2024: $851 thousand) to interest expense.

(b)Credit risk

The Group’s only customer is GIAG in Switzerland, which represents 100% of trade receivables and total revenue. Although the Group has not experienced significant problems with the collection of receivables, a significant change in the creditworthiness of GIAG could have a material adverse effect on the Group’s consolidated financial position.

(c)Liquidity risk

The Group’s credit profile and funding sources ensure that sufficient liquid funds are maintained to meet its liquidity requirements. As part of its liquidity management, the Group closely monitors and plans for its future capital expenditure well ahead of time.
v3.25.2
Fair value measurement
 6 Months Ended
Jun. 30, 2025
Fair value measurement  
Fair value measurement

15.Fair value measurement

The Group has assessed that the fair values of cash and cash equivalents, trade and other receivables, trade and other payables and accrued liabilities and other current liabilities approximate their carrying amounts largely due to the short-term maturities of these instruments.

The Group’s investment in a listed entity is fair valued by Level 1 inputs utilising quoted prices (unadjusted) in active markets for identical assets.

The fair value of the Group’s long-term loans and borrowings are determined using Level 2 inputs utilising contractual cash flows, interest rate curves, swaption volatilities, and the Group’s implied credit spread.

15.Fair value measurement (continued)

The following table shows the carrying values, fair values and fair value hierarchy of the Group’s financial instruments as at 30 June 2025 and 31 December 2024:

​

​

​

​

​

​

​

​

​

​

​

​

​

    

​

    

30 June 2025

    

31 December 2024

US$ thousand

​

Level

​

Carrying value

    

Fair value

​

Carrying value

    

Fair value

Financial assets

 

  

 

  

 

  

 

  

 

  

Fair value through profit or loss

 

​

​

​

 

​

 

​

 

​

Cash and cash equivalents

 

1

​

102,109

 

102,109

 

171,897

 

171,897

Investments

 

1

 

5,538

 

5,538

 

3,984

 

3,984

Trade and other receivables

 

1

 

14,904

 

14,904

 

7,310

 

7,310

Total financial assets

​

​

​

122,551

​

122,551

​

183,191

​

183,191

​

​

​

​

​

​

​

​

​

​

​

Financial liabilities

 

​

 

​

 

​

 

​

 

​

Amortised cost

​

​

​

​

​

​

​

​

​

​

Trade and other payables

 

​

 

79,742

 

79,742

 

51,050

 

51,050

Lease liability

 

​

 

7,444

 

7,444

 

10,233

 

10,233

Loans and borrowings

 

2

 

367,576

 

389,440

 

403,191

 

414,526

Other financial liabilities (excluding contingent consideration)

 

​

 

225

 

225

 

328

 

328

​

​

​

​

454,987

​

476,851

​

464,802

​

476,137

Fair value through profit or loss

 

​

 

  

 

  

 

  

 

  

Other financial liabilities (contingent consideration)

 

  

 

  

 

  

 

  

 

  

Royalty deed

 

3

 

46,515

 

46,515

 

47,661

 

47,661

Contingent copper consideration

 

3

 

119,590

 

119,590

 

94,050

 

94,050

Derivative financial liabilities

 

  

 

​

 

​

 

​

 

​

Mezz Warrants

​

3

 

14,835

 

14,835

 

11,066

 

11,066

Mezzanine debt facility embedded

 

  

 

​

 

​

 

​

 

​

derivative

 

2

 

—

 

—

 

34,713

 

34,713

Silver stream embedded derivative

 

3

 

34,112

 

34,112

 

16,163

 

16,163

Copper stream embedded derivative

 

3

 

8,081

 

8,081

 

5,182

 

5,182

Commodity swap liability

 

2

 

18,708

 

18,708

 

12,120

 

12,120

​

​

​

​

241,841

​

241,841

​

220,955

​

220,955

Total financial liabilities

 

  

 

696,828

 

718,692

 

685,757

 

697,092

​

There have been no transfers between the different fair value hierarchy levels in any of the periods presented in these interim financial statements.

​

15.Fair value measurement (continued)

Derivative instruments

The following table shows the fair values of the Group’s derivative financial assets and liabilities as at 30 June 2025 and 31 December 2024:

​

​

​

​

​

​

​

​

​

    

​

    

30 June

    

31 December

US$ thousand

​

Note

​

2025

    

2024

​

​

​

​

​

​

​

Derivative financial liabilities

 

  

 

  

 

  

Current

 

  

 

  

 

  

Silver stream embedded derivative

 

(a)

 

5,090

 

2,566

Copper stream embedded derivative

 

(b)

 

1,924

 

981

Mezzanine debt facility embedded derivative

​

(d)

 

—

 

11,587

Commodity swap liability

​

(e)

​

18,708

​

7,045

​

​

​

​

25,722

​

22,179

Non-current

 

  

 

​

 

​

Silver stream embedded derivative

 

(a)

 

29,022

 

13,597

Copper stream embedded derivative

 

(b)

 

6,157

 

4,201

Warrants

​

(c)

 

14,835

 

11,066

Mezzanine debt facility embedded derivative

​

(d)

 

—

 

23,126

Commodity swap liability

​

(e)

​

—

​

5,075

​

​

​

 

50,014

 

57,065

Total derivative financial liabilities

​

​

 

75,736

 

79,244

​

(a)Silver stream embedded derivative

The silver stream embedded derivative is measured at fair value through profit or loss and valued using a silver future curve simulation valuation model at each reporting date.

The significant unobservable inputs used in the fair value measurement of the embedded derivative pertains to the anticipated silver deliveries. In isolation, a significant increase (decrease) in anticipated silver deliveries would result in a significantly lower (higher) fair value measurement. In addition to estimation of the Group’s anticipated deliveries of silver over the term of the agreement, the following key inputs were used for the valuation of the embedded derivative:

​

​

​

​

​

​

​

​

​

    

30 June

    

31 December

​

​

​

2025

​

2024

  

Silver spot price (per oz)

​

36.11

​

$

28.91

 

Own credit spread

​

8.32

%  

​

7.99

%  

​

In isolation, at 30 June 2025, a 5% increase in silver price (per oz) would result in a $5,304 thousand increase and a 5% decrease in silver price (per oz) would result in a $5,304 thousand decrease in the fair value of the silver stream embedded derivative liability (31 December 2024: a $4,421 thousand increase and a $4,421 thousand decrease in the fair value of the silver stream embedded derivative liability).

15.Fair value measurement (continued)

Derivative instruments (continued)

(a)Silver stream embedded derivative (continued)

The following table presents the continuity schedule for the silver stream embedded derivative for each of the following periods:

​

​

​

​

​

​

​

​

Six months ended 30 June

US$ thousand

    

2025

    

2024

​

​

​

​

​

Balance as of beginning of period

 

16,163

 

(3,090)

Change in fair value

 

17,949

 

18,652

Balance as of end of period

 

34,112

 

15,562

​

(b)Copper stream embedded derivative

The copper stream embedded derivative is measured at fair value through profit or loss and valued using a copper future curve simulation valuation model at each reporting date.

The significant unobservable inputs used in the fair value measurement of the embedded derivative pertains to the anticipated copper deliveries. In isolation, a significant increase (decrease) in anticipated copper deliveries would result in a significantly lower (higher) fair value measurement. In addition to estimation of the Group’s anticipated deliveries of copper over the term of the agreement, the following key inputs were used for the valuation of the compound embedded derivative:

​

​

​

​

​

​

​

​

​

​

    

30 June

    

31 December

  

​

​

2025

​

2024

​

Copper spot price (per tonne)

​

$

10,040

​

$

8,653

 

Copper price volatility

​

 

21.55

%  

​

23.55

%

Own credit spread

​

 

9.00

%  

​

8.67

%

​

In isolation, at 30 June 2025, a 5% increase in copper price (per tonne) would result in a $4,695 thousand increase and a 5% decrease in copper price (per tonne) would result in a $4,741 thousand decrease in the fair value of the copper stream embedded derivative liability (31 December 2024: a $4,488 thousand increase and a $4,525 thousand decrease in the fair value of the net copper stream embedded derivative liability).

​

The following table presents the continuity schedule for the copper stream embedded derivative for each of the following periods:

​

​

​

​

​

​

​

    

Six months ended 30 June

US$ thousand

​

2025

​

2024

​

​

​

​

​

Balance as of beginning of period

 

5,182

 

(773)

Initial recognition

 

—

 

—

Change in fair value

 

2,899

 

8,946

Balance as of end of period

 

8,081

 

8,173

​

(c)Warrants

​

​

​

​

​

​

​

​

​

    

​

    

Private

    

​

​

​

​

​

Placement

​

​

US$ thousand

​

Public Warrants

​

Warrants

​

Mezz Warrants

​

​

​

​

​

​

​

For six months ended 30 June 2025

​

​

​

​

​

​

Balance as of beginning of period

 

—

 

—

 

11,066

Change in fair value

 

—

 

—

 

3,769

Balance as of end of period

 

—

 

—

 

14,835

​

15.Fair value measurement (continued)

Derivative instruments (continued)

(c)Warrants (continued)

​

​

​

​

​

​

​

​

​

    

​

    

Private

    

​

​

​

​

​

Placement

​

​

​

​

Public Warrants

​

Warrants

​

Mezz Warrants

For six months ended 30 June 2024

 

  

 

  

 

  

Balance as of beginning of period

 

15,113

 

11,176

 

16,906

Change in fair value

 

22,655

 

16,754

 

1,436

Redemption of warrants

 

(37,768)

 

(27,930)

 

—

Balance as of end of period

 

—

 

—

 

18,342

​

The Company’s Public Warrants, Private Placement Warrants and Mezz Warrants did not meet the “fixed for fixed” criteria under IAS 32 Financial Instruments: Presentation (“IAS 32”) and were classified and accounted for as derivative liabilities at fair value through profit or loss.

During the comparative period ended 30 June 2024, the Company redeemed all of the Public Warrants and Private Placement Warrants for a redemption price of US$0.10 per warrant and issued ordinary shares of the Company having par value of US$0.0001 per share (refer to Note 17). As of 30 June 2025 and 31 December 2024, no Public Warrants and no Private Placement Warrants were outstanding.

The fair value of the Mezz Warrants is determined using a Monte Carlo simulation model. As of 30 June 2025, there were 3,187,500 Mezz Warrants outstanding (31 December 2024: 3,187,500).

​

The following assumptions were used for the valuation of the Mezz Warrants. The significant unobservable inputs in the fair value measurement are the expected life of the Mezz Warrants and the expected volatility based on comparable publicly traded companies.

​

​

​

​

​

​

​

​

​

​

    

30 June

    

31 December

  

​

​

2025

​

2024

​

Risk-free rate

 

​

4.19

% 

​

4.02

%

Warrant expected life

 

​

3 years

 

​

3.5 years

 

Expected volatility

 

​

56.10

% 

​

49.23

%

Expected dividend yield

 

​

0

% 

​

0

%

Share price (US$)

​

$

12.25

​

$

10.62

​

​

Significant increases (decreases) in any of these inputs in isolation would result in a significantly higher (lower) fair value measurement. Generally, a change in the assumption used for the expected volatility is accompanied by a directionally opposite change in the assumption used for the expected life of the Mezz Warrants.

(d)Mezzanine debt facility embedded derivative

The mezzanine debt facility embedded derivative was measured at fair value through profit or loss and valued using a Monte-Carlo simulation model in relation to the future copper price and incorporation of the Longstaff-Schwartz algorithm to value the prepayment option. The key inputs in the valuation technique included the risk-free rate, copper price volatility, copper price forward curve, and the Company’s credit spread.

During the period, the mezzanine debt facility embedded derivatives were derecognised upon the settlement of mezzanine debt facility (refer Note 11).

​

15.Fair value measurement (continued)

Derivative instruments (continued)

(e)Commodity swap liability

​

On 15 June 2023, the Company entered into commodity swap agreements with Citibank, Bank of Montreal (“BMO”) and National Bank of Canada (“NBC”) respectively. The underlying commodity of the three commodity swap agreements is Copper, and the purpose of the commodity swaps is to hedge the price risk of the scheduled Copper production. Commodity swap agreements have not been designated in a hedge relationship, they act as an economic hedge and will offset the underlying transactions when they occur.

During the period, on 16 April 2025, the commodity swap agreement with NBC was novated in such a way that NBC transferred all of its rights, liabilities, duties and obligation obligations under the agreement to Westpac Banking Corporation (“Westpac”).

The commodity swap agreements are summarised below:

​

​

​

​

​

​

​

​

​

​

​

Counterparty

    

Citibank

    

BMO

    

Westpac / NBC

​

​

​

​

​

​

​

​

​

​

Effective date

​

​

1 July 2023

​

​

1 July 2023

​

​

1 July 2023

Termination date

​

​

31 May 2026

​

​

30 May 2026

​

​

31 May 2026

Total notional quantity (MT)

​

 

12,255

​

 

12,255

​

 

12,255

Fixed price (US$)

​

 

8,204.49

​

 

8,214.35

​

 

8,112.85

Reference price

​

LME cash settlement price for Copper

Settlement frequency

​

 

Monthly

​

 

Monthly

​

 

Monthly

​

As the agreements meet the definition of a derivative, each contract is measured at fair value through profit or loss.

Contingent consideration

The following table shows the fair values of the Group’s contingent consideration payable as at 30 June 2025 and 31 December 2024:

​

​

​

​

​

​

​

​

​

    

​

    

30 June

    

31 December

US$ thousand

​

Note

​

2025

​

2024

Royalty deed

 

(a)

 

46,515

 

47,661

Contingent copper consideration

 

(b)

 

119,590

 

94,050

​

​

​

 

166,105

 

141,711

​

(a)Royalty deed

Pursuant to the Net Smelter Returns (“NSR”) royalty agreement entered in connection with the acquisition of CMPL, the contingent consideration is recognised at fair value through profit and loss and valued at each reporting date using the present value of expected cash flows and timing of the NSR over the expected life of the CSA mine using an effective interest rate of 8%. The NSR is determined using consensus copper prices less estimated treatment and refining costs under the offtake agreement with Glencore Operations Australia Pty Ltd (“Glencore”). The discount rate of 8% takes into consideration the risks in the cash flow forecast and the cost of debt. A significant increase (decrease) in the discount rate, in isolation, would result in a significant lower (higher) fair value measurement.

​

15.Fair value measurement (continued)

Contingent consideration (continued)

(a)Royalty deed (continued)

The following table presents the continuity schedule for the royalty deed for each of the following periods:

​

​

​

​

​

​

​

    

Six months ended 30 June

US$ thousand

    

2025

    

2024

​

​

​

​

​

Balance as of beginning of period

 

47,661

 

43,985

Change in fair value

 

1,304

 

7,213

Royalty accruals and payments

 

(2,450)

 

(4,778)

Balance as of end of period

 

46,515

 

46,420

​

(b)Contingent copper consideration

The contingent copper consideration, in connection with the acquisition of CMPL, comprises two tranches of US$75 million payable to Glencore depending on the average daily London Metal Exchange closing price of copper exceeding the defined thresholds. Based on the average daily London Metal Exchange closing price of copper, the first US$75 million payment was triggered subsequent to the period end on 20 August 2025 (refer Note 20). As per the terms of the CMPL Share Sale Agreement and Intercreditor Deed, the first contingent payment is not payable (other than from free cashflow and after satisfaction of all operating costs and debt servicing) until one business day after the three-year anniversary of when MAC originally acquired CMPL, being 17 June 2026. Accordingly, as at the reporting date, the first tranche of the contingent copper consideration in included in current liabilities.

The contingent copper consideration is recognised at fair value through profit and loss and valued using a Monte Carlo simulation model at each reporting date. The fair value for each contingent component is the result of the average expected payoff of all simulation iterations discounted to the present value at the risk-free borrowing rate. The change in fair value is dependent on the movement in copper prices and the change in the risk-free borrowing rate.

The following key inputs were used for the valuation of the contingent copper consideration. The significant unobservable input in the fair value measurement is the reversion factor. A significant increase (decrease) in the reversion factor, in isolation, would result in a significantly higher (lower) fair value measurement.

​

​

​

​

​

​

​

​

​

​

    

30 June

    

31 December

    

​

​

2025

​

2024

​

​

​

​

​

​

​

​

​

Long-term copper price

​

$

4.20

 

$

4.25

 

Copper spot price

​

$

4.56

 

$

3.92

 

Annual price volatility

​

 

20.12

%  

​

20.70

%  

Annual inflation rate

​

 

1.00

%  

​

1.07

%  

Risk-free rate

​

 

4.49

%  

​

4.72

%  

Reversion factor

​

 

11.55

%  

​

11.55

%  

​

The following table presents the continuity schedule for the contingent copper consideration for each of the following periods:

​

​

​

​

​

​

​

​

Six months ended 30 June

US$ thousand

    

2025

    

2024

Balance as of beginning of period

 

94,050

 

84,200

Change in fair value

 

25,540

 

10,200

Balance as of end of period

 

119,590

 

94,400

​
v3.25.2
Liability for cash-settled share-based payments
 6 Months Ended
Jun. 30, 2025
Liability for cash-settled share-based payments  
Liability for cash-settled share-based payments

16.Liability for cash-settled share-based payments

During the period ended 30 June 2025, MAC’s Board resolved that, in case of the Scheme (refer Note 1) becoming legally effective, all outstanding restricted stock units (“RSUs”) and performance stock units (“PSUs”) granted under the Long-Term Incentive Plan (whether unvested or vested) will be cancelled with each RSU and PSU holder getting a cash consideration equal to the product of in the case of RSUs, the Scheme Consideration and the total number of RSUs held; and in the case of PSUs, the Scheme Consideration and the total number of PSUs held multiplied by 2.25; and all outstanding deferred share units (“DSUs”) granted under the Non-Employee Director DSU Plan will be automatically redeemed, on the Scheme implementation date when the DSU holder resigns as a Director, against a cash consideration equal to the product of the Scheme Consideration and the total number of DSUs held.

At the reporting date, management considered the implementation of the Scheme more likely than not and determined the fair values of these cash settled share-based payments as at 30 June 2025 as if the Scheme will be implemented. The Company has recorded the associated liability as non-current at 30 June 2025 on the basis that until the conditions precedent in respect of the Scheme, including shareholder approval are resolved, the Company has the right to defer the settlement of these liabilities for 12 months at 30 June 2025.
v3.25.2
Share capital
 6 Months Ended
Jun. 30, 2025
Share capital  
Share capital

17.Share capital

Issue of ordinary shares

During the period ended 30 June 2025, MAC redeemed a total of 88,040 restricted stock units (“RSU”) held by senior management of the Company under the Long - Term Incentive Plan and issued equivalent ordinary shares thereagainst.

During the comparative period ended 30 June 2024:

●On 20 February 2024, MAC issued 19,117,648 Chess Depositary Interests (“CDIs”) via the successful IPO on the ASX, at a price of AU$17.00 per CDI, for aggregate gross proceeds of approximately AU$325,000 thousand (US$211,708 thousand) and incurred shares issuance costs of US$6,912 thousand.
●On 10 June 2024, MAC redeemed all of its Public Warrants and Private Placement Warrants and issued 4,701,071 ordinary shares thereagainst (refer to Note 15).
●On 14 June 2024, MAC redeemed 17,284 DSUs held by non-employee directors of the Company under the Non-Employee DSU Plan and issued equivalent ordinary shares thereagainst.
v3.25.2
Related party disclosures
 6 Months Ended
Jun. 30, 2025
Related party disclosures  
Related party disclosures

18.Related party disclosures

Key management personnel compensation

For the six months ended 30 June 2025, key management personnel compensation comprised short-term employee benefits, post-employment benefits and share-based payments of $13,856 thousand with the share based payments component reflecting the valuation assumption as per Note 16 assuming the Scheme (refer Note 1) becoming legally effective (six months ended 30 June 2024: $6,132 thousand).
v3.25.2
Commitments and contingencies
 6 Months Ended
Jun. 30, 2025
Commitments and contingencies  
Commitments and contingencies

19.Commitments and contingencies

Registration rights

The holders of the (i) founder shares (which were issued in a private placement prior to the closing of the U.S. IPO), (ii) Private Placement Warrants (which were issued in a private placement simultaneously with the closing of the U.S. IPO) and (iii) Private Placement Warrants (that were issued upon conversion of Working Capital Loans) will have registration rights to require the Company to register a sale of any of the securities held by them pursuant to the A&R Registration Rights Agreement so long as such demand includes a number of registrable securities with a total offering price in excess of $50,000 thousand. The holders of these securities are entitled to make up to three demands in any 12-month period, excluding short form demands, that the Company register such securities. In addition, the holders have certain “piggy-back” registration rights with respect to registration statements filed in the U.S. subsequent to the completion of the CMPL acquisition. The Company will bear the expenses incurred in connection with the filing of any such registration statements.

Rehabilitation bond

MAC is required to provide performance guarantees to the state of New South Wales (“NSW”) equivalent to the estimated total amount required to fulfil any rehabilitation costs associated with CMPL mining activities.

Upon the acquisition of CMPL, Glencore was subject to contractual commitments whereby it had agreed to provide these performance guarantees for up to AU$44,031 thousand until the earlier of MAC refinancing its senior debt and MAC replacing Glencore’s performance guarantee provided to NSW. Whilst Glencore had provided the performance guarantees, MAC and MAC Australia were to assume all liability if the guarantees were called on.

During the period, on 27 March 2025, MAC utilised the new letter of credit Facility C of $45,000 thousand added to the SFA (refer Note 11) to replace Glencore’s performance guarantees in relation to the rehabilitation costs associated with CMPL mining activities.

As at 30 June 2025 the total value of the rehabilitation bonds amounted to AU$44,031 thousand (31 December 2024: AU$44,683 thousand).

Capital commitments

Capital expenditure for the acquisition of property, plant and equipment is generally funded through the cash flow generated by the business. As at 30 June 2025, $13,806 thousand all of which relates to expenditure to be incurred over the next year (31 December 2024: $10,749 thousand) was contractually committed for the acquisition of plant and equipment.

Environmental contingencies

The Group’s operations are subject to various environmental laws and regulations. The Group is in material compliance with those laws and regulations. The Group accrues for environmental contingencies when such contingencies are probable and reasonably estimable. Such accruals are adjusted as new information develops or circumstances change. Recoveries of environmental remediation costs from insurance companies and other parties are recorded as assets when the recoveries are virtually certain. At this time, the Group is unaware of any material environmental incidents at the CSA mine. Any potential liability arising from the above is not expected to have a material adverse effect on the Group’s income, financial position or cash flow.
v3.25.2
Subsequent events
 6 Months Ended
Jun. 30, 2025
Subsequent events  
Subsequent events

20.Subsequent events

Harmony Transaction

Subsequent to the period end and up to the date of approval of these financial statements, the following progress has been made in relation to the Harmony Transaction (refer Note 1):

●On 22 July 2025, MAC announced that:

-

MAC has entered into restructuring documents with Harmony, OR Royalties Limited (formerly Osisko Bermuda Limited) and Glencore (as applicable) pursuant to which the parties have agreed to amend various documents in connection with the copper stream, the silver stream and the royalty deed, with such amendments to take effect after the Scheme has been implemented.

●On 31 July 2025, MAC announced that:
-the Court has made orders, among other things, that MAC:
oconvene a meeting of eligible shareholders to consider and vote on a resolution to approve the Scheme (“Court Meeting”); and
oconvene a meeting of MAC shareholders immediately after the Court Meeting to approve certain other matters in connection with the implementation of the Transaction (“General Meeting”).

-

The Court also approved the dispatch of a scheme circular, which, among other things, contains full details of the Scheme (the “Scheme Circular”).

●On 5 August 2025, MAC announced that the Scheme Circular has been dispatched on 4 August 2025 and made available on MAC’s website.
●On 8 August 2025, MAC announced that MAC has been notified by Harmony that Harmony has received written confirmation from the Financial Surveillance Department of the South African Reserve Bank that it has no objection to the implementation of the Scheme and Harmony’s intended funding of the Scheme Consideration.
●On 18 August 2025, MAC announced that MAC has been notified by Harmony that Harmony has received written notice on behalf of the Australian Federal Treasurer stating that the Commonwealth Government does not object to the Scheme and that all the regulatory conditions to the Scheme have been satisfied.
●The Court Meeting and the General Meeting are scheduled for 29 August 2025.

Contingent copper consideration

The contingent copper consideration, in connection with the acquisition of CMPL, comprises two tranches of US$75 million payable to Glencore depending on the average daily London Metal Exchange closing price of copper exceeding the defined thresholds. Based on the average daily London Metal Exchange closing price of copper, the first US$75 million payment was triggered subsequent to the period end on 20 August 2025. As per the terms of the CMPL Share Sale Agreement and Intercreditor Deed, the first contingent payment is not payable (other than from free cashflow and after satisfaction of all operating costs and debt servicing) until one business day after the three-year anniversary of when MAC originally acquired CMPL, being 17 June 2026.

There have been no other events subsequent to balance sheet date which would have a material effect on the Group’s interim financial statements for the six months ended 30 June 2025.
v3.25.2
Segment information (Tables)
 6 Months Ended
Jun. 30, 2025
Segment information  
Segment information

​

​

​

​

​

​

​

​

Six months ended 30 June

US$thousand

    

2025

    

2024

​

​

​

​

​

Loss after tax

 

(76,686)

 

(102,169)

Income tax (benefit)/expense

 

(2,514)

 

7,066

Net finance costs

 

51,830

 

31,799

Net change in fair value of financial instruments

 

57,298

 

109,323

Operating profit

 

29,928

 

46,019

Depreciation and amortisation

 

37,882

 

38,365

Organisational restructuring expenses

 

—

 

988

IPO and transaction costs1

 

2,717

 

2,615

Other significant expenses2

 

10,693

 

2,582

Adjusted EBITDA

 

81,220

 

90,569

1 related to the ASX IPO, acquisition of the CSA Copper Mine, refinancing and other investment decisions

2 includes discretionary bonuses and share based payments that would be due if the Scheme is implemented
v3.25.2
Revenue (Tables)
 6 Months Ended
Jun. 30, 2025
Revenue  
Schedule of revenue

​

​

​

​

​

​

​

​

Six months ended 30 June

US$ thousand

    

2025

    

2024

Sale of commodities - Copper

 

156,456

 

176,270

Sale of commodities - Silver

 

6,772

 

5,890

Total

 

163,228

 

182,160
v3.25.2
Finance income and costs (Tables)
 6 Months Ended
Jun. 30, 2025
Finance income and costs  
Summary of finance income and costs

​

​

​

​

​

​

​

​

Six months ended 30 June

US$ thousand

    

2025

    

2024

Finance income

 

  

 

  

Interest income

 

1,639

 

766

Realised gain on sale of investments

 

1,548

 

—

Foreign exchange gain

​

—

​

886

Total finance income

 

3,187

 

1,652

​

​

​

​

​

Finance costs

 

  

 

  

Interest expense under the effective interest rate method on:

 

  

 

  

– Loans and borrowings

 

(33,176)

 

(26,303)

– Lease liabilities

 

(446)

 

(725)

Debt extinguishment and modification costs

​

(12,469)

​

—

Unwinding of discount on rehabilitation provision

​

(412)

​

(532)

Commodity swap loss

​

(7,794)

​

(5,714)

Realised loss on warrants redemption

​

—

​

(148)

Realised loss on copper and silver streams

​

(145)

​

(29)

Foreign exchange loss

 

(575)

 

—

Total finance costs

 

(55,017)

 

(33,451)

​

​

​

​

​

Net change in fair value measurements of financial instruments

 

  

 

  

Change in fair value of:

 

  

 

  

– Warrant liability

 

(3,769)

 

(40,845)

– Equity instruments

​

750

​

(495)

– Embedded derivative – copper and silver streams

 

(20,848)

 

(27,598)

– Embedded derivative – mezzanine debt facility

 

—

 

185

– Contingent liability – royalty deed

​

(1,304)

​

(7,213)

– Contingent liability – copper consideration

​

(25,540)

​

(10,200)

– Commodity swap liability

​

(6,587)

​

(23,157)

Total net change in fair value of financial instruments

 

(57,298)

 

(109,323)

​

​

​

​

​

Net finance costs

 

(109,128)

 

(141,122)

​
v3.25.2
Income Taxes (Tables)
 6 Months Ended
Jun. 30, 2025
Income taxes  
Schedule of amounts recognised in profit or loss

​

​

​

​

​

​

​

​

Six months ended 30 June

US$ thousand

    

2025

    

2024

Current income tax expense

 

4,996

 

3,521

​

 

4,996

 

3,521

​

​

​

​

​

Deferred tax (benefit)/expense

 

​

 

​

Origination and reversal of temporary differences

 

(7,510)

 

3,545

​

 

(7,510)

 

3,545

Total income tax (benefit)/expense

 

(2,514)

 

7,066

​
v3.25.2
Inventories (Tables)
 6 Months Ended
Jun. 30, 2025
Inventories  
Summary of total inventories

​

​

​

​

​

​

​

    

30 June

    

31 December

US$ thousand

​

2025

    

2024

Current

 

  

 

  

Supplies and consumables

 

13,545

 

11,601

Work in progress

 

2,782

 

1,890

Finished goods

 

18,205

 

14,488

Total current

 

34,532

 

27,979

​

​

​

​

​

Non-current

 

  

 

  

Supplies and consumables

 

185

 

222

Total non-current

 

185

 

222

Total inventories

 

34,717

 

28,201
v3.25.2
Loans and borrowings (Tables)
 6 Months Ended
Jun. 30, 2025
Loans and borrowings  
Summary of carrying amounts of the Group's loans and borrowings

​

​

​

​

​

​

​

    

30 June

    

31 December

US$ thousand

​

2025

    

2024

Current

 

  

 

  

Senior syndicated facility

 

21,328

 

38,644

Copper stream

 

10,726

 

10,275

Silver stream

 

10,201

 

9,347

​

 

42,255

 

58,266

​

​

​

​

​

Non-current

 

  

 

  

Mezzanine debt facility

 

—

 

95,003

Senior syndicated facility

 

194,492

 

116,032

Copper stream

 

75,250

 

75,636

Silver stream

 

55,579

 

58,254

​

 

325,321

 

344,925

​

 

367,576

 

403,191
Summary of continuity schedule of loans and borrowings

The following table presents the continuity schedule of loans and borrowings during the period ended 30 June 2025:

​

​

​

​

US$ thousand

​

Carrying amount

Balance as of 1 January 2025

 

403,191

Drawdowns

 

​

Drawdown of senior syndicated facility

 

66,000

Arrangement fee deducted from drawdown

 

(3,275)

​

​

​

Repayments

 

​

Mezzanine debt facility

 

(112,984)

Copper and silver delivered against copper and silver stream

 

(11,549)

​

​

​

Other movements

 

​

Debt extinguishment and modification costs

 

12,469

Amortisation expense

 

13,724

Balance as of 30 June 2025

​

367,576
Summary of repayments of loans and borrowings

​

​

​

​

​

    

Six months ended

US$ thousand

​

30 June 2025

Repayment - Mezzanine debt facility

​

112,984

Repayment - Mezzanine debt facility embedded derivative (Note 15)

​

32,355

Total repayment before interest and costs

​

145,339

​

​

​

Accrued interest up to the date of repayment

​

3,652

Additional prepayment interest per the terms of early settlement

​

10,597

Other costs related to settlement

​

1,068

Total repayment

​

160,656

​
v3.25.2
Provisions (Tables)
 6 Months Ended
Jun. 30, 2025
Provisions  
Schedule of provisions

​

​

​

​

​

​

​

​

​

    

Employee

    

Rehabilitation

    

​

US$ thousand

    

entitlements

    

costs

    

Total

Balance as of 1 January 2025

 

14,606

 

19,298

 

33,904

Released

​

(1,395)

​

—

​

(1,395)

Additions

​

—

​

622

​

622

Accretion

​

—

​

412

​

412

Movements from foreign exchange impact

​

464

​

—

​

464

Balance as of 30 June 2025

​

13,675

​

20,332

​

34,007

​

​

​

​

​

​

​

Current

​

12,413

​

—

​

12,413

Non-current

​

1,262

​

20,332

​

21,594

Balance as of 30 June 2025

​

13,675

​

20,332

​

34,007

​
v3.25.2
Other financial liabilities (Tables)
 6 Months Ended
Jun. 30, 2025
Other financial liabilities.  
Schedule of other financial liabilities

​

​

​

​

​

​

​

    

30 June

    

31 December

US$ thousand

​

2025

    

2024

Current

 

  

 

  

Contingent consideration

 

86,050

 

23,680

Royalty liability

​

5,785

​

5,592

Financial liabilities arising from sale and leaseback transaction

 

225

 

213

​

​

92,060

​

29,485

​

 

​

 

​

Non-current

​

​

​

​

Contingent consideration

 

33,540

 

70,370

Royalty liability

​

40,730

​

42,069

Financial liabilities arising from sale and leaseback transaction

 

—

 

115

​

 

74,270

 

112,554

​

​

166,330

​

142,039

​
v3.25.2
Financial instruments and financial risk management (Tables)
 6 Months Ended
Jun. 30, 2025
Financial instruments and financial risk management  
Summary of carrying amounts of the Group's foreign currency denominated monetary assets and monetary liabilities

​

​

​

​

​

​

​

​

​

    

Australian

    

​

    

​

Local currency thousand

​

Dollar

​

Euro

​

Total

30 June 2025

 

  

 

  

 

  

Cash and cash equivalents

 

37,550

 

—

 

37,550

Trade and other receivables

 

1,806

 

—

 

1,806

Trade and other payables

 

(57,315)

 

—

 

(57,315)

Lease liabilities

 

(11,365)

 

—

 

(11,365)

Total

 

(29,324)

 

—

 

(29,324)

​

 

​

 

​

 

​

31 December 2024

​

​

​

​

​

​

Cash and cash equivalents

​

76,497

​

—

​

76,497

Trade and other receivables

​

661

​

—

​

661

Trade and other payables

​

(48,024)

​

(25)

​

(48,049)

Lease liabilities

​

(16,460)

​

—

​

(16,460)

Total

​

12,674

​

(25)

​

12,649
Summary of estimated sensitivity to a 10% increase (decrease) in the U.S. dollar against the relevant foreign currencies

​

​

​

​

​

​

​

​

30 June

​

31 December

US$ thousand

​

2025

    

2024

Australian Dollar

 

  

 

  

Profit or loss

 

(1,921)

 

788

​

​

​

​

​

Other

 

  

 

  

Profit or loss

 

—

 

(2)
v3.25.2
Fair value measurement (Tables)
 6 Months Ended
Jun. 30, 2025
Fair value measurement  
Summary of carrying values, fair values and fair value hierarchy of the Group's financial instruments

​

​

​

​

​

​

​

​

​

​

​

​

​

    

​

    

30 June 2025

    

31 December 2024

US$ thousand

​

Level

​

Carrying value

    

Fair value

​

Carrying value

    

Fair value

Financial assets

 

  

 

  

 

  

 

  

 

  

Fair value through profit or loss

 

​

​

​

 

​

 

​

 

​

Cash and cash equivalents

 

1

​

102,109

 

102,109

 

171,897

 

171,897

Investments

 

1

 

5,538

 

5,538

 

3,984

 

3,984

Trade and other receivables

 

1

 

14,904

 

14,904

 

7,310

 

7,310

Total financial assets

​

​

​

122,551

​

122,551

​

183,191

​

183,191

​

​

​

​

​

​

​

​

​

​

​

Financial liabilities

 

​

 

​

 

​

 

​

 

​

Amortised cost

​

​

​

​

​

​

​

​

​

​

Trade and other payables

 

​

 

79,742

 

79,742

 

51,050

 

51,050

Lease liability

 

​

 

7,444

 

7,444

 

10,233

 

10,233

Loans and borrowings

 

2

 

367,576

 

389,440

 

403,191

 

414,526

Other financial liabilities (excluding contingent consideration)

 

​

 

225

 

225

 

328

 

328

​

​

​

​

454,987

​

476,851

​

464,802

​

476,137

Fair value through profit or loss

 

​

 

  

 

  

 

  

 

  

Other financial liabilities (contingent consideration)

 

  

 

  

 

  

 

  

 

  

Royalty deed

 

3

 

46,515

 

46,515

 

47,661

 

47,661

Contingent copper consideration

 

3

 

119,590

 

119,590

 

94,050

 

94,050

Derivative financial liabilities

 

  

 

​

 

​

 

​

 

​

Mezz Warrants

​

3

 

14,835

 

14,835

 

11,066

 

11,066

Mezzanine debt facility embedded

 

  

 

​

 

​

 

​

 

​

derivative

 

2

 

—

 

—

 

34,713

 

34,713

Silver stream embedded derivative

 

3

 

34,112

 

34,112

 

16,163

 

16,163

Copper stream embedded derivative

 

3

 

8,081

 

8,081

 

5,182

 

5,182

Commodity swap liability

 

2

 

18,708

 

18,708

 

12,120

 

12,120

​

​

​

​

241,841

​

241,841

​

220,955

​

220,955

Total financial liabilities

 

  

 

696,828

 

718,692

 

685,757

 

697,092
Summary of fair values of the Group's derivative financial assets and liabilities

​

​

​

​

​

​

​

​

​

    

​

    

30 June

    

31 December

US$ thousand

​

Note

​

2025

    

2024

​

​

​

​

​

​

​

Derivative financial liabilities

 

  

 

  

 

  

Current

 

  

 

  

 

  

Silver stream embedded derivative

 

(a)

 

5,090

 

2,566

Copper stream embedded derivative

 

(b)

 

1,924

 

981

Mezzanine debt facility embedded derivative

​

(d)

 

—

 

11,587

Commodity swap liability

​

(e)

​

18,708

​

7,045

​

​

​

​

25,722

​

22,179

Non-current

 

  

 

​

 

​

Silver stream embedded derivative

 

(a)

 

29,022

 

13,597

Copper stream embedded derivative

 

(b)

 

6,157

 

4,201

Warrants

​

(c)

 

14,835

 

11,066

Mezzanine debt facility embedded derivative

​

(d)

 

—

 

23,126

Commodity swap liability

​

(e)

​

—

​

5,075

​

​

​

 

50,014

 

57,065

Total derivative financial liabilities

​

​

 

75,736

 

79,244
Summary of fair values of the contingent consideration

​

​

​

​

​

​

​

​

​

    

​

    

30 June

    

31 December

US$ thousand

​

Note

​

2025

​

2024

Royalty deed

 

(a)

 

46,515

 

47,661

Contingent copper consideration

 

(b)

 

119,590

 

94,050

​

​

​

 

166,105

 

141,711
Royalty deed  
Fair value measurement  
Summary of a continuity schedule for liabilities

​

​

​

​

​

​

​

    

Six months ended 30 June

US$ thousand

    

2025

    

2024

​

​

​

​

​

Balance as of beginning of period

 

47,661

 

43,985

Change in fair value

 

1,304

 

7,213

Royalty accruals and payments

 

(2,450)

 

(4,778)

Balance as of end of period

 

46,515

 

46,420
Contingent copper consideration  
Fair value measurement  
Summary of a key inputs were used for the valuation of assets

​

​

​

​

​

​

​

​

​

​

    

30 June

    

31 December

    

​

​

2025

​

2024

​

​

​

​

​

​

​

​

​

Long-term copper price

​

$

4.20

 

$

4.25

 

Copper spot price

​

$

4.56

 

$

3.92

 

Annual price volatility

​

 

20.12

%  

​

20.70

%  

Annual inflation rate

​

 

1.00

%  

​

1.07

%  

Risk-free rate

​

 

4.49

%  

​

4.72

%  

Reversion factor

​

 

11.55

%  

​

11.55

%  
Summary of a continuity schedule for liabilities

​

​

​

​

​

​

​

​

Six months ended 30 June

US$ thousand

    

2025

    

2024

Balance as of beginning of period

 

94,050

 

84,200

Change in fair value

 

25,540

 

10,200

Balance as of end of period

 

119,590

 

94,400

​
Warrants  
Fair value measurement  
Summary of warrants

​

​

​

​

​

​

​

​

​

    

​

    

Private

    

​

​

​

​

​

Placement

​

​

US$ thousand

​

Public Warrants

​

Warrants

​

Mezz Warrants

​

​

​

​

​

​

​

For six months ended 30 June 2025

​

​

​

​

​

​

Balance as of beginning of period

 

—

 

—

 

11,066

Change in fair value

 

—

 

—

 

3,769

Balance as of end of period

 

—

 

—

 

14,835

​

​

​

​

​

​

​

​

​

    

​

    

Private

    

​

​

​

​

​

Placement

​

​

​

​

Public Warrants

​

Warrants

​

Mezz Warrants

For six months ended 30 June 2024

 

  

 

  

 

  

Balance as of beginning of period

 

15,113

 

11,176

 

16,906

Change in fair value

 

22,655

 

16,754

 

1,436

Redemption of warrants

 

(37,768)

 

(27,930)

 

—

Balance as of end of period

 

—

 

—

 

18,342
Summary of assumptions used for valuation of liabilities

​

​

​

​

​

​

​

​

​

​

    

30 June

    

31 December

  

​

​

2025

​

2024

​

Risk-free rate

 

​

4.19

% 

​

4.02

%

Warrant expected life

 

​

3 years

 

​

3.5 years

 

Expected volatility

 

​

56.10

% 

​

49.23

%

Expected dividend yield

 

​

0

% 

​

0

%

Share price (US$)

​

$

12.25

​

$

10.62

​
Commodity swap liability  
Fair value measurement  
Summary of fair values of the Group's derivative financial assets and liabilities

​

​

​

​

​

​

​

​

​

​

​

Counterparty

    

Citibank

    

BMO

    

Westpac / NBC

​

​

​

​

​

​

​

​

​

​

Effective date

​

​

1 July 2023

​

​

1 July 2023

​

​

1 July 2023

Termination date

​

​

31 May 2026

​

​

30 May 2026

​

​

31 May 2026

Total notional quantity (MT)

​

 

12,255

​

 

12,255

​

 

12,255

Fixed price (US$)

​

 

8,204.49

​

 

8,214.35

​

 

8,112.85

Reference price

​

LME cash settlement price for Copper

Settlement frequency

​

 

Monthly

​

 

Monthly

​

 

Monthly
Silver stream embedded derivative  
Fair value measurement  
Summary of a key inputs were used for the valuation of assets

​

​

​

​

​

​

​

​

​

    

30 June

    

31 December

​

​

​

2025

​

2024

  

Silver spot price (per oz)

​

36.11

​

$

28.91

 

Own credit spread

​

8.32

%  

​

7.99

%  
Summary of a continuity schedule for embedded derivative assets

​

​

​

​

​

​

​

​

Six months ended 30 June

US$ thousand

    

2025

    

2024

​

​

​

​

​

Balance as of beginning of period

 

16,163

 

(3,090)

Change in fair value

 

17,949

 

18,652

Balance as of end of period

 

34,112

 

15,562
Copper stream embedded derivative  
Fair value measurement  
Summary of a key inputs were used for the valuation of assets

​

​

​

​

​

​

​

​

​

​

    

30 June

    

31 December

  

​

​

2025

​

2024

​

Copper spot price (per tonne)

​

$

10,040

​

$

8,653

 

Copper price volatility

​

 

21.55

%  

​

23.55

%

Own credit spread

​

 

9.00

%  

​

8.67

%
Summary of a continuity schedule for embedded derivative assets

​

​

​

​

​

​

​

    

Six months ended 30 June

US$ thousand

​

2025

​

2024

​

​

​

​

​

Balance as of beginning of period

 

5,182

 

(773)

Initial recognition

 

—

 

—

Change in fair value

 

2,899

 

8,946

Balance as of end of period

 

8,081

 

8,173
v3.25.2
Corporate information (Details) - MAC copper limited - MAC Australia
Jun. 16, 2023
$ / shares
Corporate information  
Percentage of issued share capital acquired 100.00%
Cash consideration $ 12.25
v3.25.2
Basis of accounting (Details) - USD ($)
$ in Thousands
Jun. 30, 2025
Dec. 31, 2024
Basis of accounting    
Current assets (liabilities) $ 112,929 $ 21,808
v3.25.2
Segment information (Details)
$ in Thousands
 6 Months Ended
Jun. 30, 2025
USD ($)
segment
Jun. 30, 2024
USD ($)
Segment information    
Number of operating segment | segment 1  
Loss after tax $ (76,686) $ (102,169)
Income tax benefit/(expense) 2,514 (7,066)
Net finance costs (109,128) (141,122)
Net change in fair value of financial instruments (57,298) (109,323)
Operating profit 29,928 46,019
Material reconciling items    
Segment information    
Income tax benefit/(expense) (2,514) 7,066
Net finance costs 51,830 31,799
Net change in fair value of financial instruments 57,298 109,323
Operating profit 29,928 46,019
Depreciation and amortization 37,882 38,365
Organizational restructuring expenses   988
IPO and transaction costs1 2,717 2,615
Other significant expenses2 (10,693) (2,582)
Adjusted EBITDA $ 81,220 $ 90,569
v3.25.2
Revenue - Narratives (Details)
$ in Thousands
 6 Months Ended
Jun. 30, 2025
USD ($)
T
$ / lb
Jun. 30, 2024
USD ($)
Dec. 31, 2024
T
$ / lb
Revenue      
Total $ 163,228 $ 182,160  
Copper metal tonnes payable | T 11,826.73   9,949.32
Average provisional price per tonne | $ / lb 9,551.84   9,140.24
Copper      
Revenue      
Total $ 156,456 176,270  
Sliver      
Revenue      
Total $ 6,772 $ 5,890  
v3.25.2
Finance income and costs (Details) - USD ($)
$ in Thousands
 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Finance income    
Interest income $ 1,639 $ 766
Realised gain on sale of investments 1,548  
Foreign exchange gain   886
Total finance income 3,187 1,652
Finance costs    
Interest expense under the effective interest rate method on:- Loans and borrowings (33,176) (26,303)
Interest expense under the effective interest rate method on:- Lease liabilities (446) (725)
Debt extinguishment and modification costs (12,469)  
Unwinding of discount on rehabilitation provision (412) (532)
Commodity swap loss (7,794) (5,714)
Realised loss on warrants redemption   (148)
Realised loss on copper and silver streams (145) (29)
Foreign exchange loss (575)  
Finance costs (55,017) (33,451)
Net change in fair value measurements of financial assets and liabilities    
Net change in fair value of financial instruments (57,298) (109,323)
Net finance costs (109,128) (141,122)
Warrant liability    
Net change in fair value measurements of financial assets and liabilities    
Net change in fair value of financial instruments (3,769) (40,845)
Embedded derivative - copper and silver stream agreements    
Net change in fair value measurements of financial assets and liabilities    
Net change in fair value of financial instruments (20,848) (27,598)
Embedded derivative - mezzanine debt facility    
Net change in fair value measurements of financial assets and liabilities    
Net change in fair value of financial instruments   185
Contingent liability - royalty deed    
Net change in fair value measurements of financial assets and liabilities    
Net change in fair value of financial instruments (1,304) (7,213)
Contingent liability - copper consideration    
Net change in fair value measurements of financial assets and liabilities    
Net change in fair value of financial instruments (25,540) (10,200)
Commodity swaps    
Net change in fair value measurements of financial assets and liabilities    
Net change in fair value of financial instruments (6,587) (23,157)
Equity instruments    
Net change in fair value measurements of financial assets and liabilities    
Net change in fair value of financial instruments $ 750 $ (495)
v3.25.2
Income Taxes - Amounts recognised in profit or loss (Details) - USD ($)
$ in Thousands
 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Income taxes    
Current income tax expense $ 4,996 $ 3,521
Deferred tax (benefit)/expense - Origination and reversal of temporary differences (7,510) 3,545
Income tax benefit $ (2,514) $ 7,066
v3.25.2
Inventories (Details) - USD ($)
$ in Thousands
Jun. 30, 2025
Dec. 31, 2024
Current    
Supplies and consumables $ 13,545 $ 11,601
Work in progress 2,782 1,890
Finished goods 18,205 14,488
Total current 34,532 27,979
Non-current    
Supplies and consumables 185 222
Total non-current 185 222
Total inventories $ 34,717 $ 28,201
v3.25.2
Inventories - Additional Information (Details) - USD ($)
$ in Thousands
 6 Months Ended 12 Months Ended
Jun. 30, 2025
Dec. 31, 2024
Inventories    
Write-downs of inventory recognised $ 0 $ 0
Allowance for obsolete stock $ 700 $ 700
v3.25.2
Property, plant and equipment (Details) - USD ($)
$ in Thousands
 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Property, plant and equipment    
Additions $ 32,759 $ 28,723
Depreciation on property, plant and equipment 37,882 34,096
Mine development    
Property, plant and equipment    
Additions 14,022 11,318
Construction in progress    
Property, plant and equipment    
Additions $ 18,706 $ 17,149
v3.25.2
Loans and borrowings (Details) - USD ($)
$ in Thousands
Jun. 30, 2025
Dec. 31, 2024
Loans and borrowings    
Current $ 42,255 $ 58,266
Non-current 325,321 344,925
Total 367,576 403,191
Mezzanine debt facility    
Loans and borrowings    
Non-current   95,003
Senior syndicated facility    
Loans and borrowings    
Current 21,328 38,644
Non-current 194,492 116,032
Copper stream    
Loans and borrowings    
Current 10,726 10,275
Non-current 75,250 75,636
Silver stream    
Loans and borrowings    
Current 10,201 9,347
Non-current $ 55,579 $ 58,254
v3.25.2
Loans and borrowings - Continuity schedule of loans and borrowings (Details)
$ in Thousands
 6 Months Ended
Jun. 30, 2025
USD ($)
Loans and borrowings  
Beginning balance $ 403,191
Drawdown of senior syndicated facility 66,000
Arrangement fee deducted from drawdown (3,275)
Debt extinguishment and modification costs 12,469
Amortisation expense 13,724
Ending balance 367,576
Mezzanine debt facility  
Loans and borrowings  
Repayment of loans and borrowings (112,984)
Copper and silver stream  
Loans and borrowings  
Repayment of loans and borrowings $ (11,549)
v3.25.2
Loans and borrowings - Narrative (Details) - USD ($)
$ in Thousands
 6 Months Ended
Mar. 13, 2025
Jun. 30, 2025
Mar. 27, 2025
Mar. 12, 2025
Loans and borrowings        
Proceeds from loans and borrowings   $ 62,725    
Senior Syndicated Facility Agreement        
Loans and borrowings        
Repayments of amount deferred $ 159,000      
Principal amount 125,000     $ 25,000
Margin rate (as a percent)       3.00%
Proceeds from loans and borrowings $ 66,000      
Senior Syndicated Facility Agreement | Minimum        
Loans and borrowings        
Margin rate (as a percent) 2.50%      
Senior Syndicated Facility Agreement | Maximum        
Loans and borrowings        
Margin rate (as a percent) 3.00%      
Letter of credit        
Loans and borrowings        
Principal amount $ 45,000   $ 45,000  
Mezzanine debt facility        
Loans and borrowings        
Repayment of loans and borrowings   $ 112,984    
v3.25.2
Loans and borrowings - Settlement (Details) - USD ($)
$ in Thousands
 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Loans and borrowings    
Total repayment before interest and costs $ 145,339 $ 45,441
Accrued interest up to the date of repayment 3,652  
Additional prepayment interest per the terms of early settlement 10,597  
Other costs related to settlement 1,068  
Total repayment 160,656  
Mezzanine debt facility    
Loans and borrowings    
Repayments 112,984  
Mezzanine debt facility | Embedded derivative - mezzanine debt facility    
Loans and borrowings    
Repayments $ 32,355  
v3.25.2
Provisions (Details)
$ in Thousands
 6 Months Ended
Jun. 30, 2025
USD ($)
Disclosure of other provisions [line items]  
Beginning of net book value $ 33,904
Released (1,395)
Additions 622
Accretion 412
Movements from foreign exchange impact 464
Ending of net book value 34,007
Current 12,413
Non-current 21,594
Employee Entitlements  
Disclosure of other provisions [line items]  
Beginning of net book value 14,606
Released (1,395)
Movements from foreign exchange impact 464
Ending of net book value 13,675
Current 12,413
Non-current 1,262
Rehabilitation Costs  
Disclosure of other provisions [line items]  
Beginning of net book value 19,298
Additions 622
Accretion 412
Ending of net book value 20,332
Non-current $ 20,332
v3.25.2
Other financial liabilities (Details) - USD ($)
$ in Thousands
Jun. 30, 2025
Dec. 31, 2024
Other financial liabilities.    
Contingent consideration - current $ 86,050 $ 23,680
Royalty liability - current 5,785 5,592
Financial liabilities arising from sale and leaseback transaction - current 225 213
Other financial liabilities - current 92,060 29,485
Contingent consideration - noncurrent 33,540 70,370
Royalty liability - noncurrent 40,730 42,069
Financial liabilities arising from sale and leaseback transaction - noncurrent   115
Other financial liabilities - noncurrent 74,270 112,554
Total other financial liabilities $ 166,330 $ 142,039
v3.25.2
Financial instruments and financial risk management - Market risk, Commodity price risk (Details) - Commodity price risk - USD ($)
$ in Thousands
 6 Months Ended 12 Months Ended
Jun. 30, 2025
Dec. 31, 2024
Financial instruments and financial risk management    
Percentage of reasonably possible increase (decrease) in risk assumption 10.00%  
Increase (decrease) in profit and loss due to reasonably possible increase (decrease) in designated risk component $ 11,297 $ 9,094
v3.25.2
Financial instruments and financial risk management - Market risk, Currency risk (Details) - USD ($)
$ in Thousands
Jun. 30, 2025
Dec. 31, 2024
Financial instruments and financial risk management    
Foreign currency denominated monetary assets $ 122,551 $ 183,191
Financial liability 696,828 685,757
Net assets 479,803 555,493
Currency risk    
Financial instruments and financial risk management    
Net assets (29,324) 12,649
Currency risk | Cash and cash equivalents    
Financial instruments and financial risk management    
Foreign currency denominated monetary assets 37,550 76,497
Currency risk | Trade and other receivables    
Financial instruments and financial risk management    
Foreign currency denominated monetary assets 1,806 661
Currency risk | Trade and other payables    
Financial instruments and financial risk management    
Financial liability (57,315) (48,049)
Currency risk | Lease liabilities    
Financial instruments and financial risk management    
Financial liability (11,365) (16,460)
Currency risk | Australian Dollar    
Financial instruments and financial risk management    
Net assets (29,324) 12,674
Currency risk | Australian Dollar | Cash and cash equivalents    
Financial instruments and financial risk management    
Foreign currency denominated monetary assets 37,550 76,497
Currency risk | Australian Dollar | Trade and other receivables    
Financial instruments and financial risk management    
Foreign currency denominated monetary assets 1,806 661
Currency risk | Australian Dollar | Trade and other payables    
Financial instruments and financial risk management    
Financial liability (57,315) (48,024)
Currency risk | Australian Dollar | Lease liabilities    
Financial instruments and financial risk management    
Financial liability $ (11,365) (16,460)
Currency risk | Euro    
Financial instruments and financial risk management    
Net assets   (25)
Currency risk | Euro | Trade and other payables    
Financial instruments and financial risk management    
Financial liability   $ (25)
v3.25.2
Financial instruments and financial risk management - Market risk, Currency risk, sensitivity analyses (Details) - Currency risk - USD ($)
$ in Thousands
 6 Months Ended 12 Months Ended
Jun. 30, 2025
Dec. 31, 2024
Financial instruments and financial risk management    
Percentage of reasonably possible increase (decrease) in risk assumption 10.00%  
Australian Dollar    
Financial instruments and financial risk management    
Increase (decrease) in profit and loss due to reasonably possible increase (decrease) in designated risk component $ (1,921) $ 788
Other    
Financial instruments and financial risk management    
Increase (decrease) in profit and loss due to reasonably possible increase (decrease) in designated risk component   $ (2)
v3.25.2
Financial instruments and financial risk management - Market risk, Interest rate risk (Details) - Interest rate risk - USD ($)
$ in Thousands
 6 Months Ended 12 Months Ended
Jun. 30, 2025
Dec. 31, 2024
Financial instruments and financial risk management    
Percentage of reasonably possible increase (decrease) in risk assumption 1.00%  
Increase (decrease) in interest expense due to reasonably possible increase (decrease) in designated risk component $ 563 $ 851
v3.25.2
Financial instruments and financial risk management - Credit risk (Details)
 6 Months Ended
Jun. 30, 2025
Credit risk | Glencore  
Financial instruments and financial risk management  
Percentage of trade receivables 100.00%
v3.25.2
Fair value measurement (Details) - USD ($)
$ in Thousands
Jun. 30, 2025
Dec. 31, 2024
Fair value measurement    
Financial assets, carrying value $ 122,551 $ 183,191
Financial assets, fair value 122,551 183,191
Financial liability 696,828 685,757
Financial liabilities, fair value 718,692 697,092
Financial liabilities measured at amortised cost    
Fair value measurement    
Financial liability 454,987 464,802
Financial liabilities, fair value 476,851 476,137
Financial liabilities at fair value through profit or loss    
Fair value measurement    
Financial liability 241,841 220,955
Financial liabilities, fair value 241,841 220,955
Trade and other payables | Financial liabilities measured at amortised cost    
Fair value measurement    
Financial liability 79,742 51,050
Financial liabilities, fair value 79,742 51,050
Lease liability | Financial liabilities measured at amortised cost    
Fair value measurement    
Financial liability 7,444 10,233
Financial liabilities, fair value 7,444 10,233
Loans and borrowings | Financial liabilities measured at amortised cost | Level 2    
Fair value measurement    
Financial liability 367,576 403,191
Financial liabilities, fair value 389,440 414,526
Other financial liabilities (excluding contingent consideration) | Financial liabilities measured at amortised cost    
Fair value measurement    
Financial liability 225 328
Financial liabilities, fair value 225 328
Royalty deed | Financial liabilities at fair value through profit or loss | Level 3    
Fair value measurement    
Financial liability 46,515 47,661
Financial liabilities, fair value 46,515 47,661
Contingent copper consideration | Financial liabilities at fair value through profit or loss | Level 3    
Fair value measurement    
Financial liability 119,590 94,050
Financial liabilities, fair value 119,590 94,050
Mezz Warrants | Financial liabilities at fair value through profit or loss | Level 3    
Fair value measurement    
Financial liability 14,835 11,066
Financial liabilities, fair value 14,835 11,066
Mezzanine debt facility embedded derivative | Financial liabilities at fair value through profit or loss | Level 2    
Fair value measurement    
Financial liability   34,713
Financial liabilities, fair value   34,713
Silver stream embedded derivative | Financial liabilities at fair value through profit or loss | Level 3    
Fair value measurement    
Financial liability 34,112 16,163
Financial liabilities, fair value 34,112 16,163
Copper stream embedded derivative | Financial liabilities at fair value through profit or loss | Level 3    
Fair value measurement    
Financial liability 8,081 5,182
Financial liabilities, fair value 8,081 5,182
Commodity swap liability | Financial liabilities at fair value through profit or loss | Level 2    
Fair value measurement    
Financial liability 18,708 12,120
Financial liabilities, fair value 18,708 12,120
Cash and cash equivalents | Fair value through profit or loss | Level 1    
Fair value measurement    
Financial assets, carrying value 102,109 171,897
Financial assets, fair value 102,109 171,897
Investments | Fair value through profit or loss | Level 1    
Fair value measurement    
Financial assets, carrying value 5,538 3,984
Financial assets, fair value 5,538 3,984
Trade and other receivables | Fair value through profit or loss | Level 1    
Fair value measurement    
Financial assets, carrying value 14,904 7,310
Financial assets, fair value $ 14,904 $ 7,310
v3.25.2
Fair value measurement - Transfer between levels (Details) - USD ($)
 6 Months Ended 12 Months Ended
Jun. 30, 2025
Dec. 31, 2024
Fair value measurement    
Transfer of assets from level 1 to level 2 $ 0 $ 0
Transfer of assets from level 2 to level 1 0 0
Transfer of assets into level 3 0 0
Transfer of assets out of level 3 0 0
Transfer of liabilities from level 1 to level 2 0 0
Transfer of liabilities from level 2 to level 1 0 0
Transfer of liabilities into level 3 0 0
Transfer of liabilities out of level 3 $ 0 $ 0
v3.25.2
Fair value measurement - Fair values of the Group's derivative financial assets and liabilities (Details) - USD ($)
$ in Thousands
Jun. 30, 2025
Dec. 31, 2024
Fair value measurement    
Current derivative financial liabilities $ 25,722 $ 22,179
Non-current derivative financial liabilities 50,014 57,065
Total derivative financial liabilities 75,736 79,244
Silver stream embedded derivative    
Fair value measurement    
Current derivative financial liabilities 5,090 2,566
Non-current derivative financial liabilities 29,022 13,597
Copper stream embedded derivative    
Fair value measurement    
Current derivative financial liabilities 1,924 981
Non-current derivative financial liabilities 6,157 4,201
Warrant liability    
Fair value measurement    
Non-current derivative financial liabilities 14,835 11,066
Mezzanine debt facility embedded derivative    
Fair value measurement    
Current derivative financial liabilities   11,587
Non-current derivative financial liabilities   23,126
Commodity swap liability    
Fair value measurement    
Current derivative financial liabilities $ 18,708 7,045
Non-current derivative financial liabilities   $ 5,075
v3.25.2
Fair value measurement - Silver stream embedded derivative, key inputs were used (Details)
 6 Months Ended 12 Months Ended
Jun. 30, 2025
USD ($)
Dec. 31, 2024
USD ($)
Fair value measurement    
Percentage of assets 5.00%  
Percentage of possible decrease in unobservable assets 5.00%  
Silver stream embedded derivative | Spot price    
Fair value measurement    
Significant unobservable input, asset 36.11 28.91
Percentage of liabilities 5.00%  
Percentage of assets 5.00%  
Increase in fair value measurement liabilities $ 5,304,000 $ 4,421,000
Percentage of possible decrease in unobservable liabilities 5.00%  
Percentage of possible decrease in unobservable assets 5.00%  
Decrease in fair value measurement liabilities $ 5,304,000 $ 4,421,000
Silver stream embedded derivative | Own credit spread    
Fair value measurement    
Significant unobservable input, asset 8.32 7.99
v3.25.2
Fair value measurement - Silver stream embedded derivative, continuity schedule (Details) - Silver 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 $ 16,163 $ (3,090)
Change in fair value 17,949 18,652
Balance as of end of period $ 34,112 $ 15,562
v3.25.2
Fair value measurement - Copper stream embedded derivative, key inputs were used (Details)
$ in Thousands
 6 Months Ended 12 Months Ended
Jun. 30, 2025
USD ($)
Dec. 31, 2024
USD ($)
Fair value measurement    
Percentage of assets 5.00%  
Percentage of possible decrease in unobservable assets 5.00%  
Copper stream embedded derivative | Spot price    
Fair value measurement    
Significant unobservable input, asset 10,040 8,653
Percentage of liabilities 5.00%  
Increase in fair value measurement liabilities $ 4,695  
Percentage of possible decrease in unobservable liabilities 5.00%  
Decrease in fair value measurement liabilities $ 4,741  
Increase (decrease) in fair value measurement due to reasonably possible increase in unobservable input, assets   $ 4,488
Increase (decrease) in fair value measurement due to reasonably possible decrease in unobservable input, assets   $ 4,525
Copper stream embedded derivative | Price volatility    
Fair value measurement    
Significant unobservable input, asset 21.55 23.55
Copper stream embedded derivative | Own credit spread    
Fair value measurement    
Significant unobservable input, asset 9 8.67
v3.25.2
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
v3.25.2
Fair value measurement - Warrants schedule (Details) - USD ($)
$ in Thousands
 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Continuity schedule    
Balance, beginning of period $ 852,093  
Balance, end of period 870,025  
Public Warrants    
Continuity schedule    
Balance, beginning of period   $ 15,113
Change in fair value   22,655
Redemption of warrants   (37,768)
Private Placement Warrants    
Continuity schedule    
Balance, beginning of period   11,176
Change in fair value   16,754
Redemption of warrants   (27,930)
Mezz Warrants    
Continuity schedule    
Balance, beginning of period 11,066 16,906
Change in fair value 3,769 1,436
Balance, end of period $ 14,835 $ 18,342
v3.25.2
Fair value measurement - Warrants (Details) - $ / shares
Jun. 30, 2025
Dec. 31, 2024
Jun. 30, 2024
Fair value measurement      
Exercise price of warrants     $ 0.0001
Public Warrants And Private Placement Warrants      
Fair value measurement      
Exercise price of warrants     $ 0.1
Public Warrants      
Fair value measurement      
Warrants outstanding 0 0  
Private Placement Warrants      
Fair value measurement      
Warrants outstanding 0 0  
Mezz Warrants      
Fair value measurement      
Warrants outstanding 3,187,500 3,187,500  
v3.25.2
Fair value measurement - Warrants, assumptions used (Details)
Jun. 30, 2025
Y
$ / shares
Dec. 31, 2024
Y
$ / shares
Risk-free rate    
Fair value measurement    
Significant unobservable input, liabilities 0.0419 0.0402
Warrant expected life    
Fair value measurement    
Significant unobservable input, liabilities | Y 3 3.5
Expected volatility    
Fair value measurement    
Significant unobservable input, liabilities 0.561 0.4923
Expected dividend yield    
Fair value measurement    
Significant unobservable input, liabilities 0 0
Share price    
Fair value measurement    
Significant unobservable input, liabilities | $ / shares 12.25 10.62
v3.25.2
Fair value measurement - Commodity swap liability (Details)
 6 Months Ended
Jun. 30, 2025
$ / shares
USD ($)
item
Commodity swap liability  
Fair value measurement  
Derivative number of agreements | item 3
Citibank  
Fair value measurement  
Total notional quantity | $ 12,255
Fixed price | $ / shares 8,204.49
BMO  
Fair value measurement  
Total notional quantity | $ 12,255
Fixed price | $ / shares 8,214.35
NBC  
Fair value measurement  
Total notional quantity | $ 12,255
Fixed price | $ / shares 8,112.85
v3.25.2
Fair value measurement - Contingent consideration (Details) - USD ($)
$ in Thousands
Jun. 30, 2025
Dec. 31, 2024
Jun. 30, 2024
Dec. 31, 2023
Fair value measurement        
Contingent consideration $ 166,105 $ 141,711    
Royalty Deed        
Fair value measurement        
Contingent consideration 46,515 47,661 $ 46,420 $ 43,985
Contingent copper consideration        
Fair value measurement        
Contingent consideration $ 119,590 $ 94,050 $ 94,400 $ 84,200
v3.25.2
Fair value measurement - Contingent consideration, Royalty deed (Details) - USD ($)
$ in Thousands
 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Continuity schedule    
Balance as of beginning of period $ 141,711  
Balance as of end of period $ 166,105  
Royalty deed    
Fair value measurement    
Discount rate 8.00%  
Continuity schedule    
Balance as of beginning of period $ 47,661 $ 43,985
Change in fair value 1,304 7,213
Royalty accruals and payments (2,450) (4,778)
Balance as of end of period $ 46,515 $ 46,420
v3.25.2
Fair value measurement - Contingent consideration, Contingent copper consideration (Details) - CMPL
$ in Millions
 6 Months Ended
Jun. 30, 2025
D
Jun. 16, 2023
USD ($)
tranche
Fair value measurement    
Number of contingent payments | tranche   2
Copper contingent consideration payment amount | $   $ 75
Threshold number of business day available for non-payment of the first tranche of contingent consideration | D 1  
Number of anniversary period determined for non-payment of tranche one of the contingent consideration 3 years  
v3.25.2
Fair value measurement - Contingent consideration, Contingent copper consideration, key inputs (Details)
Jun. 30, 2025
$ / lb
Dec. 31, 2024
$ / lb
Price volatility    
Fair value measurement    
Significant unobservable input, liabilities 0.561 0.4923
Risk-free rate    
Fair value measurement    
Significant unobservable input, liabilities 0.0419 0.0402
Contingent copper consideration | Long-term price    
Fair value measurement    
Significant unobservable input, liabilities 4.2 4.25
Contingent copper consideration | Spot price    
Fair value measurement    
Significant unobservable input, liabilities 4.56 3.92
Contingent copper consideration | Price volatility    
Fair value measurement    
Significant unobservable input, liabilities 20.12 20.7
Contingent copper consideration | Annual inflation rate    
Fair value measurement    
Significant unobservable input, liabilities 1 1.07
Contingent copper consideration | Risk-free rate    
Fair value measurement    
Significant unobservable input, liabilities 4.49 4.72
Contingent copper consideration | Reversion factor    
Fair value measurement    
Significant unobservable input, liabilities 11.55 11.55
v3.25.2
Fair value measurement - Contingent consideration, Contingent copper consideration, continuity schedule (Details) - USD ($)
$ in Thousands
 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Continuity schedule    
Balance as of beginning of period $ 141,711  
Balance as of end of period 166,105  
Contingent copper consideration    
Continuity schedule    
Balance as of beginning of period 94,050 $ 84,200
Change in fair value 25,540 10,200
Balance as of end of period $ 119,590 $ 94,400
v3.25.2
Liability for cash-settled share-based payments (Details)
 6 Months Ended
Jun. 30, 2025
RSU and PSU  
Liability for cash-settled share-based payments  
Cash-settled share-based payments, multiplier 2.25
v3.25.2
Share capital (Details)
$ / shares in Units, $ in Thousands, $ in Thousands
 6 Months Ended
Jun. 14, 2024
shares
Jun. 10, 2024
shares
Feb. 20, 2024
USD ($)
shares
Feb. 20, 2024
AUD ($)
$ / shares
shares
Jun. 30, 2025
shares
Jun. 30, 2024
USD ($)
Share capital            
Proceeds from issue of share capital | $           $ 204,796
Share issuance costs | $           $ 6,912
Ordinary share            
Share capital            
Redemption of warrants (in shares)   4,701,071        
RSU | Ordinary share            
Share capital            
Redemption (in shares)         88,040  
DSU | Ordinary share            
Share capital            
Redemption (in shares) 17,284          
Chess Depositary Interests | Initial Public Offering            
Share capital            
Number of shares issued during period     19,117,648 19,117,648    
Share issue price (in dollars per share) | $ / shares       $ 17    
Proceeds from issue of share capital     $ 211,708 $ 325,000    
Share issuance costs | $     $ 6,912      
v3.25.2
Related party disclosures - Key management personnel compensation (Details) - USD ($)
$ in Thousands
 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Related party disclosures    
Key management personnel compensation $ 13,856 $ 6,132
v3.25.2
Commitments and contingencies (Details)
$ in Thousands, $ in Thousands
 6 Months Ended
Jun. 30, 2025
USD ($)
item
Jun. 30, 2025
AUD ($)
Mar. 27, 2025
USD ($)
Mar. 13, 2025
USD ($)
Dec. 31, 2024
USD ($)
Dec. 31, 2024
AUD ($)
Commitments and contingencies            
Number of demands | item 3          
Registration Rights            
Commitments and contingencies            
Offering price $ 50,000          
Rehabilitation obligations            
Commitments and contingencies            
Total value of guarantees   $ 44,031       $ 44,683
Capital expenditure commitments $ 13,806       $ 10,749  
Maximum | Glencore Operations Australia            
Commitments and contingencies            
Contractual commitment   $ 44,031        
Letter of credit            
Commitments and contingencies            
Principal amount     $ 45,000 $ 45,000    
v3.25.2
Subsequent events (Details) - CMPL
$ in Millions
 6 Months Ended
Jun. 30, 2025
D
Jun. 16, 2023
USD ($)
tranche
Subsequent events    
Number of contingent payments | tranche   2
Copper contingent consideration payment amount | $   $ 75
Threshold number of business day available for non-payment of the first tranche of contingent consideration | D 1  
Number of anniversary period determined for non-payment of tranche one of the contingent consideration 3 years