The US Court of Appeals for the Ninth Circuit has declined to overturn a 2019 decision that blocked Hudbay Minerals' Rosemont copper project in Arizona.
In addition to ESG risks linked to its extraction, cobalt is at the top of the list because only two countries are in charge of producing and refining the battery metal.
Global miners are deploying a raft of new leaching technologies that can extract low concentrations of copper from waste rock and help avoid lengthy mine permitting delays.