KoBold Metals, the exploration company backed by billionaires including Bill Gates and Sam Altman, officially broke ground on what will be Zambia’s biggest copper mine as the global hunt for critical minerals heats up.

The Mingomba mine will cost more than $2.3-billion to build, making it one of the biggest ever investment projects in the southern African nation. It will eventually produce more than 300 000 t/y of the metal, ranking it among the continent’s top sources.

“This is a demonstration that Zambia is open for business,” President Hakainde Hichilema said at a ceremony to mark the start of the shaft sinking. “Where there was nothing here, now we’re talking of shafts.”

Silicon Valley-based KoBold has used its proprietary artificial intelligence technology to turbocharge exploration at Mingomba. The company discovered a previously unknown highly concentrated copper resource deep underground, after acquiring the project in December 2022.

There’s growing consensus that there will be a significant supply shortfall by the time the mine starts producing in in a few years time, as technology like electric vehicles and data centers drive up copper demand.

Yet KoBold faces challenges in bringing Mingomba’s resources to market.

While it will be one of the largest high-grade copper mines globally, Mingomba will also be one of the deepest — at about 1 700 m below surface. The area near Zambia’s border with Democratic Republic of Congo already hosts some of the wettest underground mines in the world, requiring massive pumps to prevent flooding.

KoBold will have the final cost estimate for the mine after an engineering study is complete by early next year, KoBold president Josh Goldman said in an interview at the site.

KoBold is yet to build a mine anywhere, let alone a complex one, as its focus has so far been on discovering new deposits.

For Zambia, Mingomba bolsters Hichilema’s drive to boost investment to more than triple copper output by early in the next decade. Companies including Barrick Mining Corp and First Quantum Minerals have also recently started major expansions.