Specifications: Samarium Samarium is a chemical element with the symbol Sm and atomic number 62. Samarium is a rare earth metal, with a bright silver luster, that is reasonably stable in air; it ignites in air at 150 ¡C. Even with long-term storage under mineral oil, samarium is gradually oxidized, with a grayish-yellow powder of the oxide-hydroxide being formed. Three crystal modifications of the metal also exist, with transformations at 734 and 922 ¡C.
