Could a volcano that has been extinct for 16 million years hold the world’s largest lithium deposit? This is the certainty that volcanologists and geologists have just expressed in the journal Science Advances after examining the bowels of the McDermitt Caldera, a rock formation on the border of Nevada and Oregon, northeast of San Francisco (USA).
According to them, this 45 km long and 35 km wide zone could contain up to 120 million tons of this precious ore. Enough to meet global demand for decades for lithium, which is increasingly used to make batteries for electric cars and smartphones. The battery of a medium-sized electric car requires around 40 kg of lithium. And by 2040, around 1 million tons of this alkali metal will be needed to meet global demand.
The new white gold
At 40,000 euros per ton, we understand why every mining company on the planet talks about new white gold and listens as soon as they hear about the discovery of a new deposit. Researchers estimate that the amount of mineable lithium in the McDermitt Caldera sediments is potentially 12 times greater than the amount contained in the brines of the Salar de Uyuni in Bolivia, the largest deposit known today.
“The figures announced are significant, especially when compared with the world’s lithium reserves, estimated at 22 million tons in 2021,” emphasizes Guillaume Bertrand, mineral resources expert at the Bureau of Geological and Mining Research (BRGM). But be careful, there is a difference between an underground geological resource and the economic feasibility of extracting it. »
“Lithium is not such a rare metal and there is some everywhere in the Earth’s crust, but when we discover a deposit the question becomes whether the resource is accessible and sufficiently concentrated to be profitably exploited,” explains Alan Parte , Vice President of the French group Imerys, which specializes in natural resources. Furthermore, I understand that this project met with local resistance. »
“If we found a huge deposit under Notre-Dame, that would be a big head start for us! »
Amid the outcry from environmental groups fearing the environmental impact of this future mine, Native American communities have pointed out that the ancient volcano was on sacred land. “If we found a huge deposit of lithium under Notre-Dame Cathedral, that would be a great opportunity for us! » jokes Alan Parte.
If the McDermitt Caldera actually hosts a mineable treasure, “that would be excellent news for the United States, because we will have a serious shortage of lithium in the coming years,” recognizes the vice president of Imerys. However, in his opinion, this is not enough to call into question the project carried out by his company at the Beauvoir site in the Allier to extract lithium produced in France, a “unique deposit in Europe” that would allow the extraction of lithium in 25 years long up to 34,000 tons of lithium per year. “Despite this discovery in the United States, this French project makes sense to gain sovereignty and relocate metal production within Europe,” emphasizes Guillaume Bertrand of BRGM.
“If the United States manages to exploit this mega-reserve, America will come first and they will help themselves first,” bets the vice president of Imerys. Against the backdrop of the war in Ukraine and the trade conflict with China, MPs all agreed on Thursday on the need to secure access to several precious metals such as cobalt and lithium: “Ensuring their supply is crucial (…) for the strategic autonomy of the EU.” . »