Boussingaultite is a rare ammonium magnesium hydrated sulfate mineral of the chemical formula: (NH4)2Mg(SO4)2 · 6 H2O.
The formula of boussingaultite is that of Tutton's salts type.
It was originally described from geothermal fields in Tuscany, Italy, where it occurs together with its iron analogue mohrite,[5] but is more commonly found on burning coal dumps.
[6] The mineral possess monoclinic symmetry and forms clear, often rounded crystals.
[3] The mineral is named after the French chemist Jean-Baptiste Boussingault (1802–1887).