In the global race to secure hard-to-find minerals that help power everything from smartphones to wind turbines, California’s Mojave desert is emerging as an unlikely front line. The Colosseum mine, an abandoned gold pit, is now seen as a potential source of the rare earth elements underpinning the country’s clean energy development and technological leadership ambitions.
Once part of the first mining rush, the site’s revival for rare earth extraction epitomizes the current era, whose emphasis on copper, nickel, lithium, and rare-earth elements reflects demand created by the growth of electronics, the explosion of data centers, and green energy. Colosseum, a defunct Mojave Desert gold mine, may have a new life. If, that is, the federal government continues to authorize an intensive and environmentally destructive operation in a protected area, the Mojave National Preserve.
An Australian mining company called Dateline Resources, which specializes in North American mineral extraction, is leading the effort to restart Colosseum. In April, the federal Bureau of Land Management approved the work. The BLM’s April decision prompted opposition from Sen. Adam Schiff, a Democrat, and three Democratic congressional colleagues, There are more objections, though no legal action to date, from the National Parks Conservation Association. It argues that the National Park Service, another Interior Department agency, had taken responsibility for the land from the BLM when Congress established the preserve in 1994.
Dateline is working to show its proposed mining effort targets rare earth elements that are economically recoverable. If it does, Colosseum would become the second-ever rare earth element (REE) project in the United States. It is six miles away from the first – the Mountain Pass Mine, which is operated by the Las Vegas company MP Materials. Until July, a Chinese company had the largest ownership stake in MP. Then the Defense Department took a 15 percent stake, about double the size of the Chinese firm’s.
Even if both mines produced and refined significant quantities of ore, their output would be a tiny fraction of China’s rare-earths juggernaut. Still, they would guarantee a domestic supply, however small. The U.S. move to invest more in MP Materials than the Chinese firm demonstrates the active international competition for access to the components essential to powering a swatch of different technologies.
Magnetic, luminescent, and catalytic: rare earth metals’ properties are critical to technology
These “rare” elements are omnipresent in the signature technologies of modern life: smartphones, lithium-ion batteries, EV and e-bike motors and LEDs. But what exactly are they? A short answer: 17 metals typically found clustered together in mined ores. Their shared chemical structure and the unusual alignment of their outer electrons gives the minerals unique magnetic, luminescent, and catalytic abilities.
“They provide essential properties to many modern engineered materials, but they, in most cases, represent a very small weight percent of the product itself, and a relatively small part of the value of the product as well,” said Rod Eggert, a professor at the Colorado School of Mines.
Finding concentrated, economically profitable deposits is challenging, hence their “rare” status. The operating Mountain Pass mine in San Bernardino County has one of the highest-grade rare earth deposits in the world, with about seven to nine percent total concentrations of rare-earth elements. The elements neodymium, praseodymium, dysprosium, and terbium are particularly valuable due to their powerful magnetic properties and ability to operate at high temperatures, which make them essential for everything from electric cars to solar panels to fighter jets and missile guidance systems.