“Rio Tinto late last year began using the process to extract copper from U.S. ores that are traditionally hard to process and often become waste.

It involves using microorganisms — or “bioleaching” — to remove copper from sulphide ores. Rio Tinto is initially working at a once-dormant Gunnison Copper Corp. site in Arizona and hopes to deploy the tech elsewhere in North and South America.

The intrigue: The process ‘removes the need for traditional concentrators, smelters and refineries, significantly shortening the mine-to-market supply chain,’ today’s announcement states.

It also uses far less water — about 55% as much per unit of copper as the global industry average.”

From Axios.