A mining company is pioneering a new method to mine copper from low-grade ores in Cochise County.
Nuton, a subsidiary of multinational mining corporation Rio Tinto, produced its first copper under the new method late last year at the Johnson Camp Mine, according to a Dec. 4, 2025 press release. The technology uses naturally occurring microbes to extract copper from minerals that are difficult to process, such as chalcopyrite.
“In the future, this will really be the main mineral that has to be targeted to provide the copper that is needed,” said Harald Muller, Nuton’s chief technology officer, in an interview.
Muller said that chalcopyrite contains about 70% of the world’s copper, but that traditional techniques to mine the mineral are very energy-intensive. Nuton’s method, he said, involves adding specialized microbes and an acidic liquid to heaps of crushed chalcopyrite before extracting the pure copper from the resulting runoff.
These types of processes, known as bioleaching, are common, Muller said, but are not commonly used for low-grade ores. He said the necessary microbes are found in copper deposits.
“They are there, they occur naturally in the ore. What we’ve done is, over the years, we’ve isolated them, adapted them to the conditions, and have grown them into larger populations,” he said.
According to the press release, Nuton’s technology could achieve up to 80% less water use and up to 60% lower greenhouse gas emissions than traditional methods.
“Nuton can also extend mine life and maximize resource use by extracting value from ores that would otherwise be classified as waste, increasing yield and revenue at both new and existing mines,” the press release states.
Muller said current operations at the Johnson Camp Mine, a property owned by Gunnison Copper along Interstate 10 south of Willcox, are scaled up from earlier tests at the Kennecott mine in Utah and will be scaled up further, possibly at a different location.
During its planned four-year period at the Johnson Camp Mine, which began in March 2025, Nuton plans to produce about 30,000 tons of copper, according to the December press release.
In January, Nuton struck a two-year agreement with Amazon Web Services to supply its copper to the company’s data centers, according to a Nuton press release.
According to Nuton press releases, the company has been seeking partnerships with copper mines in Arizona and Nevada.
