Local Climate Action

A transition to a world based on renewable electricity has a potential bottleneck — the need for inexpensive and readily available rare earths.

The rare earths (actually metals) are a family of 17 elements, most of them in a row called the lanthanides in the lower part of the periodic table. According to the Department of Energy’s Critical Materials List of 2023, rare earths neodymium, dysprosium and terbium are in short-term critical demand, with praseodymium close behind.

What are they used for? Technology is moving very quickly, and uses for rare earths have multiplied and evolved in the last 30 years. The first generation of EVs used nickel-metal hydride (NiMH) batteries that included rare earths, but these were replaced by lithium-ion batteries.

The current and likely future demand for rare earths is to make magnets. NdFeB magnets (alloys of neodymium, iron, boron and other metals) are powerful and compact and have become essential parts of modern electric motors. Electric vehicle engines, wind turbines, F-35 fighter jets, robots, drones and computer disk drives all use this kind of magnet.

Unfortunately, the supply chain for rare earths and rare earth magnets is fragile and threatened by political disruptions and trade wars.

Mining and processing

Rare earth ores are clustered in a few places around the world. In descending order of size, deposits of rare earths are found in: China, Brazil, India, Australia, Russia, Vietnam, the United States and Greenland.

The rare earths tend to occur together in ore minerals. They are chemically similar to each other and hard to separate — an industrial method for separation was not invented until the 1950s.

Before 1985, a single mine and processing facility called Mountain Pass in California’s Mojave Desert produced more than half of the world’s rare earths. China began to develop its very large deposits in the 1980s; today it mines about 70% of the world’s rare earths and processes about 90% of the ore.