Gypsum

Gypsum:

Chemical Formula: CaSO4·2H2O

Gypsum is a soft calcium sulfate mineral that has many uses. It can be mined and there is even a town in Colorado named after it. Gypsum is soluble in water and unlike other salts, it becomes less soluble at higher temperatures. Crystals of Gypsum have anion water and hydrogen bonds. Gypsum has many uses including: plaster ingredient, ingredient in tennis court clay, found in mead, foot creams, drywall sheets, dentistry plaster and many others. Gypsum is derived from a geek word meaning "plaster".



Synthesis
Synthetic gypsum is recovered via flue-gas desulfurization at some coal-fired electric power plants. It can be used interchangeably with natural gypsum in some applications. Gypsum also precipitates onto brackish water membranes, a phenomenon known as mineral salt scaling, such as during brackish water desalination of water with high concentrations of calcium and sulfate. Scaling decreases membrane life and productivity. This is one of the main obstacles in brackish water membrane desalination processes, such as reverse osmosis or nanofiltration. Other forms of scaling such as calcite scaling, depending on the water source, can also be important considerations in distillation as well as in heat exchangers where either the salt solubility or salt concentration can change rapidly. A new study has found that the formation of gypsum starts off as tiny crystals of a mineral called bassanite (CaSO4•0.5H2O). This process occurs via a three-stage pathway: (1) homogeneous nucleation of nanocrystalline bassanite; (2) self-assembly of bassanite into aggregates, and (3) transformation of bassanite into gypsum.

Uses
Gypsum has many uses including: Gypsum board for drywall Used in plaster fertilizer adding hardness to water for homebrewing