Anhydrite
Pronunciation : An*hy"drite
Part of Speech : n.
Etymology : [See Anhydrous.] (Min.)
Definition : Defn: A mineral of a white a slightly bluish color, usually massive. It is anhydrous sulphate of lime, and differs from gypsum in not containing water (whence the name).
Source : Webster's Unabridged Dictionary, 1913