| Chemical Formula / Property of Gypsum | Value / Composition |
|---|---|
|
Synonyms
|
Calcium sulfate dihydrate, plaster of Paris (calcined), alabaster, selenite, gypsum rock
|
|
Typical Source / Reference
|
Natural gypsum mines, FGD gypsum (power plants), US Gypsum, Knauf, Saint-Gobain
|
|
Raw Material Source
|
Natural gypsum rock (CaSO4·2H2O) or synthetic FGD gypsum
|
|
Purity of Gypsum
|
≥ 90% CaSO4·2H2O (construction grade), ≥ 95% (high purity)
|
|
Free Moisture Content
|
≤ 10% (natural gypsum), ≤ 0.5% (FGD gypsum after drying)
|
|
Water Insoluble Matter
|
≤ 5% (construction grade), ≤ 2% (high purity)
|
|
Particle Size / Fineness
|
0–50 mm (crushed rock), or 80-150 mesh (powdered gypsum)
|
|
Purposes & Applications
|
Cement retarder (5% additive in cement), plasterboard, drywall, plaster of Paris, soil conditioner, medical casts, pottery, construction
|
|
Annual Production Quantity
|
Up to 3 million tons of gypsum per year (major mining operation)
|
