Erbium is a chemical element in the lanthanide series, with symbol Er and atomic number 68.
Erbium metal tarnishes slowly in air and burns readily to form erbium(III) oxide:
- 4 Er + 3 O2 → 2 Er2O3
Erbium will slowly react with cold water, but the reaction occurs much faster in hot water.
Erbium is a silvery-white malleable metal. It is stable in air, and does not oxidize as quickly as some other rare-earth metals. Erbium is ferromagnetic below 19 K, antiferromagnetic between 19 and 80 K and paramagnetic above 80 K.
Erbium can be purchased online. Metallium sells erbium coins.
Erbium can be prepared by reducing its oxide or salts with calcium at 1450 °C under argon atmosphere.
- Er2O3 + 3 Ca → 2 Er + 3 CaO
- Erbium chloride
- Erbium glass