valentinite

Century Dictionary and Cyclopedia

1. n. Native oxid of antimony (Sb₂O₃), occurring in orthorhombic crystals and massive, of a white to brown or pink color and adamantine luster. It has the same composition as senarmontite, but differs in crystalline form. Also called antimony-bloom.

Wiktionary

1. n. mineralogy An orthorhombic antimony oxide mineral.