List the important sources of sulphur.

List the important sources of sulphur.
Answer

Sulphur mainly exists in combined form in the earth’s crust primarily as sulphates   [gypsum (CaSO₄.2H₂O), Epsom salt (MgSO₄.7H₂O), baryte (BaSO₄)] and sulphides [(galena (PbS), zinc blends (ZnS), copper pyrites (CuFeS₂)].