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The rare-earth elements (REE), also called the rare-earth metals or rare earths, and sometimes the lanthanides or lanthanoids (although scandium and yttrium, which do not belong to this series, are usually included as rare earths), [1] are a set of 17 nearly indistinguishable lustrous silvery-white soft heavy metals. Compounds containing rare ...
Neodymium is a fairly common element in the Earth's crust for being a rare-earth metal. Most rare-earth metals are less abundant. Neodymium is classified as a lithophile under the Goldschmidt classification, meaning that it is generally found combined with oxygen. Although it belongs to the rare-earth metals, neodymium is not rare at all.
It is a rare-earth element and the eleventh member of the lanthanide series. It is a relatively soft, silvery, fairly corrosion -resistant and malleable metal. Like many other lanthanides, holmium is too reactive to be found in native form, as pure holmium slowly forms a yellowish oxide coating when exposed to air.
The term rare-earth element or rare-earth metal is often used to include the stable group 3 elements Sc, Y, and Lu in addition to the 4f elements. [8] All lanthanide elements form trivalent cations, Ln 3+, whose chemistry is largely determined by the ionic radius, which decreases steadily from lanthanum (La) to lutetium (Lu).
The study shows that more than 16 million short tons (15 billion kilograms) of rare-earth elements could be "exploited in the near future." As well as yttrium (Y), which is used in products like camera lenses and mobile phone screens, the rare-earth elements found are europium (Eu), terbium (Tb), and dysprosium (Dy). [55]
Praseodymium always occurs naturally together with the other rare-earth metals. It is the sixth-most abundant rare-earth element and fourth-most abundant lanthanide, making up 9.1 parts per million of the Earth's crust, an abundance similar to that of boron. In 1841, Swedish chemist Carl Gustav Mosander extracted a rare-earth oxide residue he ...
Rare-earth ore, shown with a United States penny for size comparison. A rare-earth mineral contains one or more rare-earth elements as major metal constituents. Rare-earth minerals are usually found in association with alkaline to peralkaline igneous complexes in pegmatites. This would be associated with alkaline magmas or with carbonatite ...
Ferrofluid on glass, with a rare-earth magnet underneath. A rare-earth magnet is a strong permanent magnet made from alloys of rare-earth elements.Developed in the 1970s and 1980s, rare-earth magnets are the strongest type of permanent magnets made, producing significantly stronger magnetic fields than other types such as ferrite or alnico magnets.