Tag Archives: Rob McEwen

Rio Tinto’s Nuton to test leaching tech at McEwen Copper’s Los Azules project

McEwen Copper’s Los Azules project in Argentina looks like becoming the latest potential leaching asset put under the Nuton® Technologies microscope after the signing of a collaboration agreement between McEwen Copper and Nuton.

The agreement, tied to an oversubscribed $81.85 million offering of McEwen Copper shares, will see Nuton, a Rio Tinto Venture, test its technology for compatibility with Los Azules copper mineralisation.

Nuton, for its part, also contributed $25 million into the funds raised by McEwen Copper.

Rio Tinto’s copper leaching technology venture has been in the headlines of late, signing deals with, among other companies, Arizona Sonoran Copper Company Inc and Lion Copper and Gold, to test out its solutions.

Nuton is aimed at growing Rio Tinto’s copper business. At its core is a portfolio of proprietary copper leach related technologies and capability – a product of almost 30 years of research and development.

Rio says the Nuton technologies offer the potential to economically unlock known low-grade copper sulphide resources, copper bearing waste and tailings, and achieve higher copper recoveries on oxide and transitional material, allowing for a significantly increased copper production outcome, according to Rio. One of the key differentiators of Nuton is the potential to deliver leading environmental performance, including more efficient water usage, lower carbon emissions, and the ability to reclaim mine sites by reprocessing mine waste, Rio claims.

McEwen Copper and Nuton will jointly undertake copper leach testing using Nuton Technologies with samples from Los Azules. McEwen Copper has agreed to grant exclusivity to Nuton for one year in the area of novel, patented or trade secret leaching technology, while it will continue its independent test work and studies using conventional leach technologies.

McEwen Copper Chief Executive, Rob McEwen, said: “We recognise the potential opportunity of using Nuton Technologies to produce copper in greater amounts, more rapidly, and with less impact on the environment and water resources. I trust that our relationship with Nuton and Rio Tinto will accelerate the process of realising the enormous potential of Los Azules.”

Rio Tinto Chief Executive Copper, Bold Baatar said: “This agreement will allow us to evaluate the potential to commercially deploy Rio Tinto’s innovative Nuton Technologies for copper leaching in McEwen Copper’s planned development of Los Azules. Our Nuton Technologies have the capacity to unlock increased copper production for Rio Tinto and our partners, with a low carbon footprint and leading environmental performance.”

The next milestones at Los Azules are the upcoming drilling season from October 2022 to June 2023, the completion of an updated preliminary economic assessment early in the March quarter, and the planned initial public offering of McEwen Copper in the first half of 2023.

Los Azules’ current copper resources are estimated at 10.2 billion pounds (4.6 Mt) at a grade of 0.48% Cu (indicated category) and an additional 19.3 billion pounds (8.8 Mt) at a grade of 0.33% Cu (inferred category).

McEwen Mining progresses gold-silver heap leach plan at Fenix

McEwen Mining looks to have found a way to prolong its operations at the El Gallo Complex in Sinaloa, Mexico, with the feasibility study for its 100%-owned Fenix project highlighting a 9.5-year operational blueprint.

Using gold and silver prices of $1,500/oz and $17/oz, McEwen has estimated an operation able to produce 26,000 oz of gold production in phase one (years one to six) and 4.2 Moz of silver-equivalent in phase two (years seven to nine-and-a-half).

Phase one comes with an initial capital bill of $42 million and an all-in sustaining cost (AISC) estimate of $1,042/oz of gold. Phase two would require a $24 million incremental capital injection in year six, with the AISC calculated at $14.28/oz of silver-equivalent.

The company’s El Gallo mine (pictured) produced 240,000 oz of gold and 125,000 oz of silver from 2012-2017, yet, due to the transition to deeper sulphide mineralisation not amenable to heap leaching, mining and crushing activities ceased in the June quarter of 2018.

While residual heap leaching is set to continue to produce gold for several years, the company has been working on a new project for the El Gallo Complex, which is where Fenix comes in.

The Fenix 2018 preliminary economic assessment evaluated the potential extension of production in the complex, based on a two-phased transformation of the processing from the El Gallo mine, innovative in-pit tailings disposal and sourcing from several deposits.

The latest feasibility study has run with that plan, with the critical path environmental permits in hand for the first phase of production, according to Rob McEwen, Chairman and Chief Owner of McEwen Mining.

“Our next steps will involve detailed engineering, assessment of procurement options and the evaluation of financing alternatives,” Rob McEwen said.

He added: “The project will incorporate an environmentally progressive method of tailings management, using in-pit storage that creates multiple benefits, most importantly a secure containment of tailings, enabling better reclamation results.”