Calcium sulphate dihydrate is a white, crystalline mineral widely recognised for its stability, low solubility, and natural abundance. It is used across construction materials, agriculture, pharmaceuticals, food processing, and laboratory applications. As gypsum, it is a key ingredient in plasters, cements, and wallboard, providing strength, workability, and controlled setting characteristics.

In agriculture, it serves as a soil conditioner supplying calcium and sulphur without altering pH. It is also used as a desiccant, a coagulant in certain food applications, and as a reagent or standard in analytical chemistry.
Impurity limits should be matched to the specific sector, especially for pharmaceutical, food, or laboratory-grade requirements.