The Periodic Label

The Rare Earths

The elemental forms of Rare Earths are typically soft, malleable, ductile and reactive. They are used in a wide variety of applications. "Earth" is an obsolete term for oxide. At the time of their discovery, earths of these elements were believed to be scarce in abundance as minerals. However, the term "rare earth" is now deprecated by IUPAC, as these elements are in fact relatively abundant in the Earth's crust: the most abundant, cerium, at 60 parts per million, is the 25th most abundant in the crust of any element, more common than lead, whilst even the least abundant "rare" earth element, lutetium, is 200 times more abundant than gold. Learn more about The Rare Earths on wikipedia.