Gypsum Mine

►Structural morphology of gypsum mine

a0=0.568nm, b0=1.518nm, c0=0.629nm, B=118°23; Z is equal to 4. The crystal structure consists of the [SO4]2 tetrahedron bonded with Ca2+ to form a 1(010) double layer, which is bonded by the H20 molecule. The complete cleavage occurs in this direction. Ca2+ has a coordination number of 8 and is bound to six 02- and two H20 molecules of the four adjacent [S04] tetrahedrons. H2O molecules are linked to O2- in [SO4] by hydrogen bonds, and water molecules are linked to each other by molecular bonds.

Rhombic cylindrical class, C2h-2/m(L2PC). The crystal is often developed into a plate, but also granular. Often simple form: parallel double-sided b,p, rhombic column m, etc.; Crystal face and often with longitudinal grain; Sometimes it is lentil-shaped. Twin crystals are common, one is the Garry twin or dovetail twin with (100) as the twin crystal face, and the other is the Paris twin or arrow twin with (101) as the twin crystal face. Most of the aggregates are dense granular or fibrous. Fine granular block is called snowflake stone; Fibrous aggregates are called fibrils. Rosettes formed from lentil crystals are rare. There are also earthy and lamellar aggregates.