Samarium is a chemical element with symbol Sm and atomic number 62. It is a moderately hard silvery metal that readily oxidizes in air. Being a typical member of the lanthanide series, samarium usually assumes the oxidation state +3.
Three reasons Samarium stands out
- 1
A rare earth metal used in powerful magnets.
- 2
Its radioactive isotope is used to relieve severe bone pain in patients with cancer that has spread to bones.
- 3
Magnets made from it were the strongest available before neodymium magnets were developed in the 1980s.
A magnet that refuses to let go
Samarium-cobalt magnets retain strength at temperatures that weaken many neodymium magnets. That resilience suits aerospace, motors, and instruments exposed to heat. Samarium also absorbs neutrons effectively, while the isotope samarium-149 records part of the operating history of natural and engineered reactors.