Name the chief forms of occurrence of magnesium in nature.

Explanation

Magnesium is quite abundant in the earth crust and occupy sixth position in order of their abundance.
Ores of magnesium: The important ores of magnesium are as follows:
(i). Carnallite:
`(2KCl.MgCl_(2).6H_(2)O) or K_(2)MgCl_(4).6H_(2)O`
(ii). Magnesite: `MgCO_(3)`
(iii). Dolomite: `MgCO_(3).CaCO_(3)CaCO_(3)`
(iv). Epsom salt: `MgSO_(4).7H_(2)O`
The chlorides and sulphates occur in sea water.