Magnesium sulfate is the primary substance that causes the absorption of sound in seawater.
1) Magnesium sulfates are common minerals in geological environments. Their occurrence is mostly connected
with processes.
2) Some of them are also important constituents of evaporitic -magnesium (K-Mg) salts deposits. Almost all known mineralogical forms of MgSO4 occur as hydrates. is the natural analogue of
"Epsom salt," mentioned above.
3) Another heptahydrate, the -containing mineral alpersite (Mg,Cu)SO4·7H2O, was also recently recognized.
4) Both are however not the highest known hydrates of MgSO4, due to the recent terrestrial find of , MgSO4·11H2O,
which is thought to also occur on Mars.