Rio2 Limited press release

Rio Tinto approves $144 million investment to advance Resolution Copper project

2026-11-05

TSX - Toronto Stock Exchange · Gold · Copper · Canada · Project Development

Rio Tinto has approved a $144 million investment by Resolution Copper (Rio Tinto share: $79 million) to advance the next phase of development at the project in Arizona, one of the world’s largest untapped copper deposits and a potential major new source of domestically produced copper for the United States.

The investment builds on the completion of the historic land exchange in March 2026, which unlocked the project’s next phase. It is additional to approximately $500 million of preliminary spending announced at that time.

The program will fund feasibility studies and final design engineering for the installation of development and production-level material handling equipment in both shafts and new water treatment facilities. It will also support ongoing exploration drilling, the purchase of underground development and production equipment as well as long-lead electrical equipment.

Approximately 50 additional roles will be created across mining, geotechnical and geological disciplines, engineering and project services.

Rio Tinto Copper Chief Executive Katie Jackson said: “Resolution Copper has the potential to supply up to 25% of America’s copper demand for decades, strengthen domestic supply chains and deliver significant economic benefits for Arizona.

“Following completion of the historic land exchange in March, this investment is another important step in advancing the project. These funds will accelerate underground development, create additional skilled roles and ensure Resolution Copper is well positioned for its next investment decision, while maintaining safe underground operations and construction.”

Located near Superior, Arizona, the deposit lies between 5,000 and 7,000 feet underground. Resolution Copper has the potential to become one of the largest copper mines in the United States, create thousands of direct and indirect jobs and contribute approximately $1 billion annually to Arizona’s economy.

About Resolution Copper

Resolution Copper is operated by Resolution Copper Mining, LLC, a joint venture owned 55% by Rio Tinto and 45% by BHP.

View source version on businesswire.com: https://www.businesswire.com/news/home/20261105436569/en/

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Category: Resolution