Rio Tinto adds $144 million to Resolution Copper project

Rio Tinto has approved $144 million in additional spending at its Resolution Copper project in Arizona, funding engineering and underground development after the venture secured the land for the proposed mine.

Why it matters: Resolution holds enough copper to supply up to a quarter of US demand for decades, so each funding step moves one of the largest undeveloped US copper sources closer to a construction decision, though permitting and Apache opposition remain unresolved.

Data as of The Northern Miner report of November 5, 2026, read in full in this run; Mining.com carried the same announcement. Developing item.

Rio Tinto has approved $144 million (C$201 million) in additional spending at Resolution Copper in Arizona, advancing engineering and underground development after the venture secured the land needed for the proposed operation. Rio, which owns 55 percent of the venture alongside BHP, contributes $79 million of the programme, which covers feasibility studies, equipment purchases and water treatment work and creates about 50 additional jobs.

The spending adds to about $500 million announced when the venture completed its land exchange in March, which transferred more than 2,400 acres near Superior to Resolution Copper. The partners still face state and local permitting, further technical work and opposition from the San Carlos Apache Tribe and Apache Stronghold over the destruction of Oak Flat, a sacred site above the deposit, and no decision has been made to begin mining.

Rio Tinto adds $144 million to Resolution Copper project

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