Generally speaking, gypsum can generally refer to raw gypsum and anhydrite. Raw gypsum is calcium sulfate dihydrate, also known as dihydrate gypsum, hydrated gypsum or anhydrite, usually in dense block or fibrous shape, with a Mohs hardness of 2; Anhydrite is anhydrous calcium sulfate with a Mohs hardness of 3-3.5. The two kinds of gypsum […]
