fatcory provide the high quality magnesium sulfate,magnesium sulfate heptahydrate fertilizer grade Magnesium Sulfate Molecular Formula: MgSO4·7H2O. Molecular weight:246.48. Characteristics: -- ... its crystal water becomes anhydrous compounds. Use: --Mainly used in fertilizer, tanning, pringting and dyeing,activator,papermaking,plastic,porcelain,pigment matchmaking ...