... , match, fireproof materials, Mg-salt, dyeing, medicine and food additives;3. Extensively used in food, pharmaceutical and animal remedy industries. ITEMSSpecialty gradesFine gradeMgSo4.7H2O ... ,%,≤11Water insoluble,%,≤0.050.05 Magnesium Sulphate Heptahydrate used in food, Medicine