... 120 mesh, 3)initial setting 7minutes ,final setting 15 gypsum powder for cement/chalk: we are the professional manufacture for gypsum ... have ourselves gypsum mine and produce three kinds of gypsum powder A,B,C at currently.A) Whiteness is 90% above ... , Final setting for 15 minutes. Useful: cornice, chalk, ceiling, contruction, casting, wall, plasterboard, food,medical bandage etc Packing: one bag is ...