valentinite

[ val-uh n-ti-nahyt, -tee-nahyt ]
/ ˈvæl ən tɪˌnaɪt, -ˌti naɪt /

noun

a mineral, antimony trioxide, Sb2O3, formed by the oxidation of various minerals containing antimony and occurring in the form of white orthorhombic crystals.

Origin of valentinite

1855–60; < German Valentinit, named after Basil Valentine, 15th-century German alchemist; see -ite1