What Are Rare Earth Minerals?

Rare earth minerals are naturally occurring substances that contain one or more of the 17 rare earth elements (REEs). Despite their name, most rare earths are relatively abundant in Earth's crust. Cerium, for example, is more common than copper. The challenge lies not in their scarcity but in finding deposits concentrated enough for economical extraction.

The 17 rare earth elements are typically divided into two groups:

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