The more abundant rare earths — lanthanum, cerium, neodymium, praseodymium.
The lighter elements in the rare earth series, including lanthanum, cerium, praseodymium, neodymium, promethium, and samarium. LREEs are more abundant than heavy rare earths but still economically important, particularly neodymium and praseodymium for permanent magnets.
Lanthanum and cerium are abundant to the point of oversupply, so a high TREO grade built on them is worth much less per tonne than the number suggests. The value inside the light group is neodymium and praseodymium.
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