Sm - Samarium
(Samarskite, a mineral) Discovered spectroscopically by its sharp absorption lines in1879 by Lecoq de Boisbaudran in the mineral samarskite, named in honor of a Russian mineofficial, Col Samarski.
Samarium is found along with other members of the rare-earth elements in many minerals,including monazite and bastnasite, which are commercial sources. It occurs in monazite tothe extent of 2.8%. While misch metal containing about 1% of samarium metal, has long beenused, samarium has not been isolated in relatively pure form until recent years.Ion-exchange and solvent extraction techniques have recently simplified separation of therare earths from one another; more recently, electrochemical deposition, using anelectrolytic solution of lithium citrate and a mercury electrode, is said to be a simple,fast, and highly specific way to separate the rare earths. Samarium metal can be producedby reducing the oxide with lanthanum.