Marada, Ajdabiya (Agedabia), Al Wahat District, Libya

SrSO₄

Crystal System: orthorhombic
Colour: colourless, light blue, white, reddish, greenish, brownish or greyish
Lustre: vitreous, pearly
Habitus: tabular
Hardness: 3 - 3½
Fracture: irregular/uneven
Cleavage: perfect on {001} and {210}, good on {010}
Density: 3.98 g/cm³ 
Origin and geological occurrence: celestine can have sedimentary origin or it can precipitate by migrating strontium-bearing ground water or basinal brines in carbonate rocks, concretions and nodules. It has also been found in hydrothermal veins and mafic volcanic rocks.

www.mindat.org
Smorf link

Samples:

	7.7 Celestine #sulfates
	7.8 Celestine Prismatic crystals of celestine with sulfur. Sicily, Italy. #sulfates