When we are saying about Gypsum, it's the dihydrate gypsum or raw gypsum stone. In the nature, gypsum exsits as a shape of stone. It's Mineral monoclinic system, the Molecular Formula is CaSO4˙2H2O. It's widely used in the area of industry and construction industry. It can be used for building interior decoration materials, ceramic molding, art work, dentistry and for some other usage.
Gypsum as well as its finished products are with a special microcellular structure that can absorb or release moisture, this enable gypsum the very good function of sound proof, temperature adjustment and fire-resistant.
The natural raw stone for gypsum exists in various colors: white, gray, brown, teal, green, orange or other. When the raw gypsum stone is cleaned and heated to 100~200℃, the dihydrate gypsum can lose part of its crystal water to become hemihydrate gypsum which is a hard condensation material in the form of Alpha or Beta gypsum plaster, the Alpha and Beta gypsum plaster are 2 different gypsum powder with different physical properties.
The Alpha hemihydrate gypsum plaster is with very good crystal, harder, higher strength, but the Beta hemihydrate gypsum plaster is with flake crack crystal, the crystal is tiny but surface area is much larger than Alpha gypsum plaster.
In the process of making gypsum powder, the Alpha type needs much less water than the Beta needs but with better consistency and strength than the Beta type.
Generally, the Alpha gypsum powder is produced in tightly sealed equipment, we also call it high strength gypsum powder, but the Beta gypsum powder is produced in open-ended equipment, we also call it building gypsum powder.
Either the Alpha or Beta gypsum plaster powder can become the dihydrate gypsum when mixed with water, they will try fast mixed with water and become hard with a certain strength rate.
