| Samarium is never found free in nature, but, like other rare earth elements, is contained in many minerals, including monazite, bastnasite and samarskite; monazite (in which it occurs up to
an extent of 2.8%) and bastnasite are also used as commercial sources. Misch metal containing about 1% of samarium has long
been used, but it was not until recent years that relatively pure samarium has been isolated through ion exchange processes,
solvent extraction techniques, and electrochemical deposition. The metal is often prepared by electrolysis of a molten mixture
of samarium(III) chloride with sodium chloride or calcium chloride. Samarium can also be obtained by reducing its oxide with lanthanum.
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Occurrence