| The use of this name is depreciated by IUPAC, as they are neither rare in abundance nor "earths" (an obsolete term for water-insoluble
strongly basic oxides of electropositive metals incapable of being smelted into metal using late 18th century technology).
These elements are in fact fairly abundant in nature, although rare as compared to the "common" earths such as lime or magnesia.
Cerium is the 26th most abundant element in the Earth's crust, neodymium is more abundant than gold and even thulium (the least common naturally-occurring lanthanoids) is more abundant than iodine.
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| The term "rare earths" arises from the minerals from which they were isolated, which were uncommon oxide-type minerals. |
| The Rare Earth Elements are made up of the Lanthanoid together with scandium and yttrium.
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| The Lanthanoid series: Lanthanum, Cerium, Praseodymium, Neodymium, Promethium, Samarium, Europium, Gadolinium, Terbium, Dysprosium, Holmium, Erbium, Thulium, Ytterbium and Lutetium.
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