... . 1. Uses: in agriculture: mainly used in mixed fertilizer or directly used as fertilizer for rubber, palm trees ;2. In industries: used ... in tanning, porcelain, pigment, match, fireproof materials, Mg-salt, dyeing ... .20As ,%,≥0.5Pb ,%,≤1Water insoluble,%,≤0.05 Magnesium Sulphate Heptahydrate fertilizer grade