Praseodymium is used cryogenic refrigeration.
Standard State: Solid at 298 K
Color: silvery white, yellowish tinge
In 1841, Mosander extracted the rare earth didymia from lanthana; in 1879, Lecoq de
Boisbaudran isolated a new earth, samaria, from didymia obtained from the mineral
samarskite. Six years later in 1885, von Welsbach separated didymia into two
other earths, praseodymium and meodymia, which gave salts of different colors.
Praseodymium can be prepared by several methods, such as by calcium reduction of the
anhydrous chloride of fluoride. Misch metal, used in making cigarette lighters, contains
about 5% praseodymium metal.