Question: what raw materials are used to make gypsum?
Answer: Slurry and Placing on Face Paper Stucco is mixed with solid additives such as potash, starch, boric acid, and glass fiber (the latter is for fire-rated wall board) and liquid additives such as retarders, foaming agents, silicone, and—most importantly—water, which rehydrates the mixture into a slurry.