Gypsum is a calcium sulphate mineral in non-metallic sulphates.

    in building materials, such as cement retarder, gypsum products for construction and cementing materials;
  • as the soil improver, fertilizer and pesticide in agriculture;
  • in papermaking, paint, rubber, ceramics, plastics, textile, food, arts and crafts, culture, education and medicine;
  • as raw materials for the manufacture of sulfuric acid and ammonium sulfate in the absence of other sulfur resources.

Two main classes of gypsum ore

Generally speaking, gypsum refers to two minerals, gypsum and anhydrite. They are often produced together and can be transformed into each other under certain geological effects.

2 main classes of gypsum ore

2 main classes of gypsum ore

Types Gypsum (Dihydrate gypsum or Plaster) Anhydrite Chemical formula CaSO4¡¤2H2O CaSO4 Chemical composition 32.6% of CaO, 46.5% of SO3, 0.9% of H2O2+ 41.2% of CaO and 58.8% of SO3 Crystal system monoclinic orthorhombic Crystal habit tabular, dense massive, fibrous tabular dense massive, granulous Color white, gray, red, brown white, off-white Luster vitreous, silky vitreous Hardness 2 3¡«3.5 Density 2.3 g/cm3 2.8¡«3.0 g/cm3 Cleavage {010} perfect {010} perfect

14 subclasses of gypsum ore

According to the crystal form, structure and material composition of gypsum, it can be further divided into the following 14 subcategories:

fibrous plaster, giant-pegmatite gypsum, gypsum, argillaceous (clay) gypsum, carbonate gypsum, anhydrite-gypsum, argillaceous (clay) anhydrite-gypsum, carbonate anhydrite-gypsum, gypsum-anhydrite, argillaceous (clay) gypsum-anhydrite, carbonate gypsum-anhydrite, anhydrite, argillaceous (clay) anhydrite and carbonate anhydrite.

14 subclasses of gypsum ore

14 subclasses of gypsum ore

Fibrous plaster is milky white or wax yellow, with a fibrous structure. Its often in the form of veins, nets, lenses or thin interlayers together with gypsum and anhydrite layers. The blue-gray giant-pegmatite gypsum ore is mainly composed of crystal clusters, granular gypsum and clay minerals.

Gypsum (or common) ore is white, green, gray or light yellow. It is massive and granular structure. Its main minerals include dihydrate, a small amount of anhydrite (the sum of the two is over 85%), and a small amount of dolomite, calcite and clay minerals.

The colorless and transparent pure gypsum is called selenite, while recrystallized fine granular aggregate is called alabaster (crystal gypsum).