Calcium sulfate, a chemical compound with the formula CaSO4, exists in various forms, but the two most common ones are gypsum (calcium sulfate dihydrate) and anhydrite (calcium sulfate anhydrous). Gypsum is a soft, white mineral often used in construction and agriculture. It is a key ingredient in plasterboard, where it provides fire resistance and soundproofing. In agriculture, gypsum is employed to improve soil structure and nutrient retention. Anhydrite, on the other hand, is a denser, less water-absorbent form of calcium sulfate and is used in industrial processes, including cement production. Both forms of calcium sulfate have distinct properties that make them valuable in a range of applications, from building materials to industrial chemistry.