U.S. Borax, part of Rio Tinto, operates California’s largest open pit mine in Boron, California—one of the richest borate deposits on the planet. And, where there is boron, you’re very likely to find lithium.
New process turns waste into lithium
In 2019, an initial small-scale trial successfully proved the process of roasting and leaching waste rock at Boron could recover high grades of lithium. Rio Tinto then created a lithium demonstration plant on site to start producing battery-grade lithium. The demo plant is the next step in scaling up a breakthrough lithium production process (developed at Boron) to recover the critical mineral and extract additional value out of waste piles from more than 90 years of mining at the operation.
The lithium plant has a design capacity of 10 tonnes per year of battery-grade lithium. It ran throughout 2021 to optimize the process and inform Rio Tinto’s feasibility assessment for progressing to a production scale plant with an initial capacity of at least 5,000 tonnes per year, or enough to make batteries for approximately 70,000 electric vehicles.