This pale pink deliquescent solid is a commercially significant manganese(II) salt.
All of these salts dissolve in water to give faintly pink solutions of the aquo complex [Mn(H2O)6]2+.
The tetrahydrate also features Mn(II) in an O6 coordination sphere provided by bridging two sulfate anions and four aquo ligands.
In the laboratory, manganese sulfate can be made by treating manganese dioxide with sulfur dioxide:[4] It can also be made by mixing potassium permanganate with sodium hydrogen sulfate and hydrogen peroxide.
[1] Manganese(II) sulfate minerals are very rare in nature and always occur as hydrates.