“Rare earth” is an alternative name for the lanthanides – elements 57 to 71 – plus yttrium and scandium. The elements are integral to modern life, and are used in everything from disc drives, hybrid cars and sunglasses to lasers and aircraft used by the military.
China controls 97 per cent of the world’s supply and has been tightening its export quotas, sparking concerns that the rare earths could live up to their name.
Now, the US Geological Survey has looked at all known national reserves of the elements as part of a larger assessment of the threat posed to defence by limited rare earth supplies.
It found that the domestic pipeline is “rather thin”. The US boasts the third largest reserves in the world after China and the Commonwealth of Independent States, made up of nations that were formerly part of the Soviet Union. But the only rare earths mine the US has ever operated, at Mountain Pass, California, is currently inactive. Mining may restart there within two years, but any other mines will be far behind.