Campiano Mine, Montieri, Grosseto Province, Tuscany, Italy

CaSO₄

Crystal System: orthorhombic
Colour: colourless, bluish, blue-grey, violet, white, pink, brownish, reddish or grey
Lustre: vitreous, greasy, pearly
Habitus: tabular or equant
Hardness: 3 - 3½
Fracture: irregular/uneven or splintery
Cleavage: perfect on {010} perfect; on {100} nearly perfect; on {001} good to imperfect.
Density: 2.95 g/cm³ 
Origin and geological occurrence: anhydrite is a major component in sedimentary evaporite deposits and in the cap rocks above salt domes, commonly formed by dehydration of gypsum. It has also been found in igneous rocks, fumarolic deposits and in seafloor hydrothermal chimneys. It is an alteration product in hydrothermal mineral deposits.

Mindat link
Smorf link

Samples:

	7.2 Anhydrite Granoblastic aggregate #sulfates
	7.3 Anhydrite Whitish tabular crystals #sulfates