rare earth

American  

noun

Chemistry.

1. the oxide of any of the rare-earth elements contained in various minerals.

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rare earth British  

noun

1. any oxide of a lanthanide

2. Also called: rare-earth element.  another name for lanthanide

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Etymology

Origin of rare earth

First recorded in 1875–80

Example Sentences

Additionally, the moon is home to water ice, which can be used for rocket propulsion, as well as rare earth minerals such as lithium, platinum and other materials critical to electronics and clean energy technology.

From BBC

An Australian company has launched a rare earths mining project just outside Joshua Tree National Park in critical desert tortoise habitat, an area the company’s director refers to as an “emerging heavy rare earth district.”

From Los Angeles Times

"An example is rare earth elements, which are very scarce on Earth, and there might be parts of the Moon where these are concentrated enough to be able to mine them."

From BBC

While China’s share of U.S. consumer-electronics imports plunged, it continued to dominate rare earths, minerals crucial to making a range of goods.

From The Wall Street Journal

Authorities will in the "near future" install scanning technology at border posts to detect undeclared rare earth minerals, Kambamura told parliament.

From Barron's