Anhydrite is a mineral composed primarily of calcium sulfate (CaSO₄) and is an important component in the formation of sedimentary rocks. It typically forms in evaporative environments, such as salt flats and lake beds, where water evaporates and leaves behind minerals. Anhydrite is usually colorless or white but can also appear in shades of gray, blue, or pink due to impurities. Unlike its hydrated counterpart, gypsum, anhydrite lacks water in its crystal structure, making it less soluble. This property allows it to persist in geological formations and contributes to the formation of gypsum when it interacts with water over time. Anhydrite is often used in construction and agriculture, particularly as a soil conditioner.