Rio Tinto has signed a final joint venture agreement with Japan’s Sumitomo Metal Mining (SMM) for the development of the Winu copper and gold project in the Great Sandy Desert, Western Australia. The deal gives SMM a 30% stake in the project for up to $430.4 million.
Under the terms, SMM will pay $195 million up front, with the remaining $235.4 million contingent on future development milestones. Rio Tinto will retain a 70% interest and continue to lead project development and operations.
The two companies signed an initial term sheet in December 2023 and have now formalised the agreement in Perth. The deal is expected to close in 2025, pending regulatory approvals and other customary conditions.
Beyond Winu, the companies have agreed to explore broader strategic collaboration in copper, base metals, and lithium, expanding on their long-standing relationship that began with the Northparkes mine in New South Wales in 2000.
The Winu deposit, discovered by Rio Tinto in 2017, is considered a low-risk, long-life asset with potential for further expansion. A prefeasibility study is expected this year, targeting initial processing capacity of up to 10 million tonnes per annum. An environmental review document is also set for submission under Western Australia’s EPA assessment process.
Rio Tinto emphasised its continued engagement with local Indigenous communities, including ongoing negotiations with the Nyangumarta and Martu Traditional Owners to formalise project agreements.
