Lynas mines the rare earths at their Mt Weld Concentration Plant in Western Australia, before shipping the materials to Malaysia for processing.

“Twice in the last decade, CEOs have had to sit up and take notice,” of that restricted supply, Lacaze said.

The first time was in 2010 during the ‘rare earths crisis’, when China cut off supply to Japan over a dispute. The second time was this year, amid the U.S.-China trade war. That has prompted Australia to hold talks with governments including the U.S. over diversifying the supply sources of the minerals. Lynas has said it is considering opening a plant in Texas.

Meanwhile, the U.S. is also trying to produce its own supply, including the Round Top project in western Texas, a joint venture between Texas Mineral Resources Corporation and USA Rare Earth. The dependence of the U.S. on Chinese rare earths “creates a strategic vulnerability for both its economy and military,” according to a U.S. government report from May 2018.

However, Lacaze noted that despite fears that China could cut off access to rare earths, the extent of Lynas’ supply means that it’s unlikely for it to be worthwhile for China to do so again. And despite the name, rare earths aren’t actually rare, she added.

“In terms of running out, we’re not running out. Rare earths are actually quite plentiful, it’s a triumph of branding,” she said. “It’s simply about being able to identify sources that are economic to develop.”

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