Epsom salt, also known as magnesia heptahydrate, is a common mineral, which belongs to hydrated sulfate without abnormal positive ions. Its chemical composition is magnesium sulfate heptahydrate (MgSO4·7H2O). When it is crystallized, it is in an orthorhombic crystal system, often forming granular or skin-like crystals, rarely forming fine needle-like or fibrous crystals. The color of the crystals is white, slightly yellow, green or pink. There are also colorless diarrhea salts.
