the deal is controversial because of tesla's choice of mining partner. glencore. glencore is one of the world's largest diversified natural- resources companies. glencore says an independent verification process ensures it does not supply cobalt from artisanal mines. but in 2019, more than a0 artisanal miners died at one of its sites. they were trespassing on the mine when two tunnels collapsed. there was one part of the site the diggers could get onto illegally ? with the help of the security guards. the guards were badly paid, so the diggers negotiated with them to get onto the mine.