... crystal1. Uses: in agriculture: mainly used in mixed fertilizer or directly used as fertilizer for rubber, palm trees ;2. In industries: used in tanning, porcelain, ... Mg-salt, dyeing, medicine and food additives;3. Extensively used in food, pharmaceutical and animal remedy industries. ITEMSSpecialty gradesFine gradeMgSo4 ... insoluble,%,≤0.050.05 Magnesium Sulphate Heptahydrate used in food, Medicine