By Jamie Hyland, MiningIR
In a move that immediately boosts its cash flow and deepens its footprint in the global copper market, Harmony Gold Mining Company Limited (“Harmony”) has entered into a definitive agreement to acquire MAC Copper Limited (“MAC”), owner of the high-grade CSA Copper Mine in New South Wales, Australia. The all-cash transaction—valued at approximately US$1.03 billion—marks a significant milestone in Harmony’s ongoing transition into a diversified, global gold and copper producer.
“The acquisition of the CSA Copper Mine in Australia is significant as it introduces a high-quality, established underground producing copper asset to the Harmony portfolio. CSA is one of the highest-grade copper mines in Australia, producing ~41kt of copper in calendar year 2024. The operation is a logical fit with the portfolio given it meets Harmony’s core investment criteria, including increasing free cash flow generation while improving margins at long-term expected commodity prices. We believe that Harmony is well positioned to leverage its expertise in underground mining to further enhance operations. Furthermore, the Transaction represents a significant step forward in transforming Harmony into an increasingly de-risked, higher-quality, global gold and copper producer through disciplined and effective capital allocation,” said Beyers Nel, Chief Executive Officer.
Strategic Rationale: Transforming Harmony into a Copper-Gold Powerhouse
With over 75 years of operational excellence, Harmony has steadily pursued a strategy of value-accretive acquisitions. This deal aligns perfectly with Harmony’s vision to expand in Tier 1 jurisdictions, strengthen cash flow, and scale high-margin copper operations. It follows a series of successful acquisitions, including Hidden Valley (PNG), Moab Khotsong (South Africa), Mponeng (South Africa), and the Eva Copper Project (Australia).
Highlights of the Transaction:
- Immediate Cash Flow: CSA produced over 41,000 tonnes of copper in 2024 with a C1 cash cost of US$1.92/lb and AISC of US$2.92/lb, delivering an operating free cash flow margin of 36%.
- De-Risked Diversification: Entry into a proven, high-grade, long-life copper asset in a politically stable jurisdiction, with reserve life exceeding 12 years and additional upside from the emerging Merrin Mine zone.
- Enhanced Copper Growth: With this acquisition and the development of Eva Copper, Harmony aims to produce approximately 100ktpa of copper on Australia’s East Coast within 5 years.
- Balance Sheet Strength: Harmony will maintain its leverage target (Net Debt/EBITDA <1.0x) post-acquisition. A bridge facility of US$1.25 billion has been secured from major global banks including Citi, JPMorgan, and Macquarie.
About CSA and MAC
CSA is one of Australia’s deepest and richest copper mines, operating at depths of 1.9km with a reserve grade of 3.4% Cu. It has a production legacy of nearly 150 years and is located near Cobar in central western New South Wales. MAC also holds 756 km² of exploration tenements and is actively developing the Merrin Mine, which is expected to commence production in Q4 2025 and includes copper and zinc zones.
In 2024, MAC reported:
- EBITDA: US$168 million
- EBITDA Margin: ~49%
- Net Assets: US$555 million
- Net Loss: US$82 million (IFRS basis)
Deal Terms & Shareholder Support
Harmony will pay US$12.25 per MAC share, representing:
- 20.7% premium to the closing price on May 23, 2025
- 32.1% premium to the 30-day VWAP
The deal will be implemented via a court-approved Scheme of Arrangement under Jersey law and is supported by MAC’s board and key shareholders (including Osisko, Sprott, Fourth Sail, Victor Smorgon, and Bluescape), who collectively control 22.5% of MAC shares.
Notably, the acquisition is not subject to Harmony shareholder approval and includes a standard suite of regulatory and commercial conditions, including Australian and South African approvals, and stream restructuring agreements with Osisko and Glencore.
Strategic Upside & Exploration Potential
Harmony plans to bring its expertise in deep underground mining to optimize CSA’s operations, implement ventilation improvements, and expand resource drilling. The development of the Merrin Mine is underway and an inaugural zinc resource was announced in February 2025, with reserves expected later this year.
Furthermore, MAC’s agreement with Glencore includes contingent payments tied to copper price thresholds—offering further upside exposure for Harmony shareholders if copper prices remain elevated.
Conclusion
This acquisition is a transformative step for Harmony, firmly positioning the company as a globally relevant, cash-flow-positive copper and gold miner. It expands Harmony’s exposure to copper—a critical energy transition metal—and strengthens its operating base in Australasia.
Subject to regulatory and shareholder approvals, the transaction is expected to close in the December Quarter 2025. Upon completion, MAC will become a wholly owned subsidiary of Harmony.
