Used as leather, explosives, paper, porcelain, fertilizer, and medical oral laxatives, etc. Mineral water additive. Magnesium sulfate is used as a fertilizer in agriculture because magnesium is one of the main components of chlorophyll. Usually used in potted plants or magnesium crops, such as tomatoes, potatoes, roses and so on. The advantage of magnesium sulfate over other fertilizers is its high solubility. Magnesium sulfate is also used as bath salt.