First Quantum Minerals (FM) has kicked off a formal process to sell a minority interest in its Taca Taca copper project in Argentina, Bloomberg reported, citing people familiar with the matter, as the Canadian miner looks to share the enormous development costs and repair its balance sheet. Potential bidders include Rio Tinto and Japanese trading houses Mitsubishi Corp. and Mitsui & Co.
The talks remain at an early stage and no deal is guaranteed, the report said. First Quantum and Rio Tinto both declined to comment.
Taca Taca, located in Salta province just 55 kilometers from the Chilean border, ranks among the world’s largest undeveloped copper deposits. Under First Quantum’s development plan, the project would require an initial capital injection of roughly $4.2 billion to process 40 million tonnes of ore per year, with a subsequent expansion to 60 million tonnes per year pushing total capital spending to around $5.25 billion.
Over its first decade of production, the mine is expected to deliver approximately 291,000 tonnes of copper annually across a 35-year mine life, reaching peak output of more than 320,000 tonnes a year — equivalent to about 1.5% of current global mine supply. Construction is forecast to create up to 4,000 jobs, with around 2,000 permanent positions once the mine enters production, alongside support for regional infrastructure and workforce development.
The stake sale unfolds against a backdrop of intensifying competition for large-scale, long-life copper assets as the world’s biggest miners bulk up on the metal critical to electrification and the energy transition. Copper prices have hovered near record highs, reinforcing expectations of future supply deficits. Argentina has emerged as a hot destination for copper investment after President Javier Milei introduced tax, customs and foreign-exchange incentives to attract mining capital, though infrastructure bottlenecks continue to pose challenges for new projects.
For First Quantum, bringing in a partner would spread the substantial capital risk of a greenfield megaproject while accelerating the company’s financial recovery from the protest-driven closure of its flagship Cobre Panamá mine in late 2023.
The miner has been steadily offloading non-core assets to concentrate capital on top-tier deposits. It sold the Las Cruces mine in Spain to Global Panduro for $190 million in December 2025, and in March this year agreed to divest the Çayeli copper-zinc mine in Turkey to Cengiz Insaat for $340 million in cash, a transaction expected to close in the second or third quarter of 2026. First Quantum already has an established relationship with Rio Tinto: in 2023, the two companies agreed to jointly develop the La Granja copper project in Peru, with First Quantum acquiring a majority interest from Rio Tinto.
