Appearance and Characteristics
Harmful effects:
Holmium is considered to be of low toxicity.
Characteristics:
Holmium is a bright, soft, silvery-white, rare earth metal that is both ductile and malleable. It does not react in dry air at normal temperatures, but rapidly oxidizes to a yellow oxide (Ho2O3) in moist air or when heated. When present in compounds, holmium exists usually in the trivalent state, Ho3+. Most holmium compounds are brownish yellow in color. Holmium has unusual magnetic properties, including the highest magnetic moment (10.6 µB) of any naturally occurring element.
Uses of Holmium
As a result of its special magnetic properties, holmium is used in alloys for the production of magnets and as a flux concentrator for high magnetic fields.
Holmia (holmium oxide) is used as a yellow or red coloring for glass and cubic zirconia.
Holmium isotopes are good neutron absorbers and are used in nuclear reactor control rods.
Holmium is also used in solid-state lasers for non-invasive medical procedures treating cancers and kidney stones.