Sodium magnesium sulfate

Sodium magnesium sulfate is a double sulfate of sodium and magnesium. There are a number of different stoichiometries and degrees of hydration with different crystal structures, and many are minerals. Members include:
 * Blödite or bloedite: sodium magnesium sulfate tetrahydrate Na2Mg(SO4)2•4H2O
 * Disodium magnesium disulfate decahydrate Na2Mg(SO4)2•10H2O
 * Disodium magnesium disulfate hexadecahydrate Na2Mg(SO4)2•16H2O
 * Na2SО4·MgSO4·2.5H2O
 * Konyaite Na2Mg(SO4)2•5H2O
 * Löweite Na12Mg7(SO4)13•15H2O.
 * Vanthoffite Na6Mg(SO4)4
 * Na2Mg2(SO4)3 langbeinite form stable from 569.2 to 624.7°C
 * Na2Mg2(SO4)3 quenched monoclinic form
 * Na2Mg3(SO4)4 orthorhombic form
 * Na2Mg(SO4)2 triclinic form

Salts containing other anions in addition to sulfate
 * Na2Mg3(OH)2(SO4)4•4H2O
 * Tychite hexasodium dimagnesium sulfate tetracarbonate Na6Mg2SO4(CO3)4
 * Uklonskovite NaMgSO4F•2H2O