samarium

A silvery or pale gray metallic rare-earth element found in monazite and bastnaesite and used as a dopant for laser materials, in infrared absorbing glass, and as a neutron absorber in certain nuclear reactors. Atomic number 62; atomic weight 150.36; melting point 1,072°C; boiling point 1,791°C; specific gravity (approximately) 7.50; valence 2, 3. See Table at element.