Rio Tinto has partnered with Chile’s state-owned miner Codelco to progress the Salar de Maricunga lithium project.
The partnership aims to develop and operate a high-grade lithium operation in the Atacama region, with Salar de Maricunga holding some of the highest-grade lithium brine in the world.
The binding agreement supports a broader strategic partnership strengthening both companies’ positions in supplying critical materials for the global energy transition.
“We aim to bring significant investment and long-term benefits to the Atacama region as we advance Maricunga and Nuevo Cobre together, with a focus on responsible sustainable development including shared infrastructure and solutions to minimise water usage,” Rio chief executive Jakob Stausholm said.
Rio Tinto plans to invest $US350 million into the venture to fund resource analysis and additional studies required to reach a final investment decision, with an additional $US500 million committed to construction costs if the project proceeds to development.
Additionally, a further $US50 million will be invested if the joint venture achieves first lithium production by the end of 2030.
The joint venture will work to update the project’s declared reserves and resources and advance the necessary studies for future investment decisions.
Rio Tinto will acquire a 49.99 per cent interest in Salar de Maricunga SpA, the entity through which Codelco holds its licenses and concessions, by funding development and study costs for the project.
The transaction is expected to close by the end of the first quarter of 2026, pending regulatory approvals and standard closing conditions.