Deep beneath the surface of the Salton Sea, a shallow lake in California’s Imperial County, sits an immense reserve of critical metals that, if unlocked, could power the state’s green economy for years to come. These naturally occurring metals are dissolved in geothermal brine, a byproduct of geothermal energy production. Now the race is on to develop technology to efficiently extract one of the most valuable metals from the brine produced by the geothermal plants near the Salton Sea: lithium.