Element category: lanthanide, sometimes considered a transition metal
Lanthanum is a soft, ductile, malleable, silver-white rare-earth element. It is a member of the lanthanide or lanthanoid series. Lanthanum is very reactive, oxidizing rapidly in air and burns easily when ignited.
Lanthanum is one of the anodic materials of nickel-metal hydride batteries used in hybrid cars. Lanthanum (III) oxide (La2O3) is used to make special optical glasses to improve the alkali resistance.