Anhydrite gypsum plaster: It is manufactured by heating gypsum to 1700C. Hemihydrate gypsum plaster: It is produced when the gypsum is heated to more than 1700 C. Gypsum plasters based on the application: Casting Gypsum Plasters. Undercoat Gypsum Plasters. Finish Gypsum Plasters. One Coat Gypsum Plasters. Machine applied Gypsum Plasters.