The alchemical symbol for sulfur is shown against a ‘fire and brimstone’ background.

Fact Box

Uses

Sulfur is used in the vulcanisation of black rubber, as a fungicide and in black gunpowder. Most sulfur is, however, used in the production of sulfuric acid, which is perhaps the most important chemical manufactured by western civilisations. The most important of sulfuric acid’s many uses is in the manufacture of phosphoric acid, to make phosphates for fertilisers.

Mercaptans are a family of organosulfur compounds. Some are added to natural gas supplies because of their distinctive smell, so that gas leaks can be detected easily. Others are used in silver polish, and in the production of pesticides and herbicides.

Sulfites are used to bleach paper and as preservatives for many foodstuffs. Many surfactants and detergents are sulfate derivatives. Calcium sulfate (gypsum) is mined on the scale of 100 million tonnes each year for use in cement and plaster.

History

Sulfur is mentioned 15 times in the Bible, and was best known for destroying Sodom and Gomorrah. It was also known to the ancient Greeks, and burnt as a fumigant. Sulfur was mined near Mount Etna in Sicily and used for bleaching cloth and preserving wine, both of which involved burning it to form sulfur dioxide, and allowing this to be absorbed by wet clothes or the grape juice. For centuries, sulfur along with mercury and salt, was believed to be a component of all metals and formed the basis of alchemy whereby one metal could be transmuted into another.

Antoine Lavoisier thought that sulfur was an element, but in 1808 Humphry Davy said it contained hydrogen. However, his sample was impure and when Louis-Josef Gay-Lussac and Louis-Jacques Thénard proved it to be an element the following year, Davy eventually agreed.