Rio Tinto's Nuton Tech Targets 1 Million Tonnes from Los Azules

Rio Tinto confirmed on June 19, 2026, that its Nuton technologies venture is targeting the extraction of an incremental one million tonnes of copper from the Los Azules deposit in Argentina. The initiative represents a strategic pivot for the mining giant to increase copper production without relying solely on new, capital-intensive greenfield projects. This move capitalizes on growing demand for the metal, which is essential for the global energy transition.

Context — [why this matters now]

Copper demand is projected to double by 2035, driven by electrification and renewable energy infrastructure. The global spot price for copper remains volatile, trading near $9,800 per tonne amidst persistent supply deficits. Major miners face increasing challenges in developing new tier-one deposits due to rising capital expenditure, regulatory hurdles, and lengthy development timelines exceeding a decade.

Rio Tinto's pursuit of technology-driven extraction echoes BHP's deployment of its BHP Xplor program in 2023, which focused on funding innovative exploration technologies for base metals. The current macro environment, with central banks signaling a higher-for-longer interest rate regime, increases the cost of capital for large-scale projects, making capital-light technological enhancements more attractive.

The immediate catalyst is the advancement of Nuton's proprietary bioleaching and agitated tank leaching processes. These technologies are designed to economically recover copper from low-grade primary sulfide ores and materials historically considered waste, turning stranded resources into viable reserves.

Data — [what the numbers show]

The Los Azules project, owned by McEwen Copper, holds an estimated inferred resource of 10.2 billion pounds of copper. Rio Tinto's Nuton investment could potentially increase the project's total recoverable copper output by over 20%. The one-million-tonne target represents a capital investment of several hundred million dollars, a fraction of the estimated $3-4 billion required for a conventional mine build-out at the site.

Nuton’s technologies have demonstrated copper recoveries above 80% in column tests on Los Azules ore, significantly higher than traditional heap leach methods. This efficiency is critical for the project's economic viability. For comparison, the average head grade of copper mines has fallen from 1.72% in 2000 to approximately 0.76% in 2025, increasing the value of technologies that can offset declining ore quality.

Rio Tinto has allocated over $1 billion to its venture capital arm, which includes Nuton, to scale such technologies across its portfolio. The company's direct copper production in 2025 was 620,000 tonnes, meaning the Los Azules target alone could represent a substantial portion of its current output.

Analysis — [what it means for markets / sectors / tickers]

Successful deployment at Los Azules would validate the Nuton business model, creating a new revenue stream for Rio Tinto (RIO) through technology licensing and joint ventures. This could provide a durable advantage over peers like BHP Group (BHP) and Freeport-McMoRan (FCX), which are also wrestling with ore grade decline. Equipment suppliers for advanced leaching systems, such as FLSmidth (FLS), could see increased demand.

A key risk is the scalability of lab-tested bioleaching processes to a full-scale commercial operation, where geotechnical and environmental variables can introduce significant cost overruns. The technology's performance in Argentina's high-altitude, cold climate at Los Azules remains a critical test.

Investment flow is moving towards miners with credible technology pathways to lower-cost production. Hedge funds have increased long positions in Rio Tinto shares by 8% over the last quarter, anticipating successful commercialization of its ventures portfolio. Short interest remains elevated in junior mining companies that lack the capital to adopt such advanced extraction methods.

Outlook — [what to watch next]

The next major catalyst is the completion of the Nuton pilot plant feasibility study for Los Azules, expected in Q4 2026. Results from this study will determine the project's technical and economic viability. Investors should monitor Rio Tinto's capital markets day in early 2027 for updated guidance on Nuton's rollout timeline and financial targets.

Key levels to watch include the sustained spot copper price above $10,000 per tonne, which would accelerate the economic case for Nuton. Any breakthrough in leaching cycle times or recovery rates reported by Rio Tinto will be a positive signal for the technology's broader application. Regulatory approval from Argentine authorities for the novel process is another critical milestone.

Frequently Asked Questions

What is Rio Tinto's Nuton technology?

Nuton is a portfolio of proprietary copper leaching technologies developed by Rio Tinto. Its core innovations involve using specialized bacteria and chemical processes to extract copper from low-grade sulfide ores that are not economical with conventional flotation methods. The technology aims to unlock billions of tonnes of copper trapped in tailings, waste rock, and low-grade deposits globally, potentially extending mine life and improving sustainability by reducing waste.

How does this affect smaller mining companies like McEwen Copper?

For junior miners like McEwen Copper, a partnership with Rio Tinto's Nuton provides access to capital and cutting-edge technology that would otherwise be unaffordable, de-risking their project development. In exchange, Rio Tinto typically secures a royalty, streaming agreement, or an equity stake, capturing value from the technology's application. This model allows majors to use their R&D while giving juniors a path to production.

What are the environmental implications of bioleaching?

Bioleaching can have a mixed environmental impact. It often requires less energy and water than traditional concentrator plants and can reduce the footprint of tailings dams. However, the process must be meticulously managed to prevent acidic drainage from affecting local water sources. Rio Tinto claims its Nuton technologies include safeguards and closed-loop systems to mitigate these risks, but independent verification at scale is pending.

Bottom Line

Rio Tinto is betting that technological innovation, not just massive excavation, will secure its future copper supply.

Disclaimer: This article is for informational purposes only and does not constitute investment advice. CFD trading carries high risk of capital loss.