By Clara Denina and Divya Rajagopal
LONDON, May 8 (Reuters) - Rio Tinto is evaluating the economic potential of McEwen Copper's giant Los Azules project in Argentina as the mining group considers increasing its 17.2% stake in the development, two industry sources said.
Los Azules is among the world's 10 largest undeveloped copper projects and the move highlights Rio Tinto's push for large-scale copper assets as miners scramble to meet surging demand from data centres and the global clean energy transition.
Rio, which owns the stake in Los Azules through its copper technology venture Nuton LLC, is also focusing on boosting organic growth through its stakes in undeveloped deposits following the collapse of merger talks with Glencore.
Its technical team is evaluating the economic potential of Los Azules, while testing Nuton's proprietary leaching technology at the site, the sources with knowledge of the matter said.
Rio Tinto declined to comment.
"We are obviously discussing with our existing partner Nuton because their technology makes so much sense," Michael Meding, managing director at Canadian miner McEwen Copper, told Reuters on Thursday.
"Now that Rio Tinto is building their copper pipeline, they basically have a mandate to add copper for their production profile. So we are having fruitful conversations."
Securing a larger stake in Los Azules would bolster Rio's copper pipeline at a time when new discoveries are scarce and competition for quality assets is fierce.
Nuton invested about $100 million for the stake in McEwen Copper, a subsidiary of McEwen Mining, according to McEwen's investor presentation in February.
A feasibility study released in October 2025 estimates an after-tax net present value of $2.9 billion, with the project targeting first production by 2030. Average production over the first five years is projected at about 204,800 metric tons per year of copper cathode.
Aside from Nuton, automaker Stellantis holds an 18.3% stake in McEwen Copper, having invested around $275 million as part of its global push to secure raw materials for electric vehicle batteries.
McEwen Copper is seeking about $4 billion in initial capital to develop the mine. The company previously said it planned an initial public offering of about $300 million toward the end of this year.
(Reporting by Clara Denina and Divya Rajagopal. Editing by Veronica Brown and Emelia Sithole-Matarise)
