Sulphur

Elemental sulphur is a bright yellow, brittle non-metal recovered either from native sulphur deposits by the Frasch process (injecting superheated water to melt and pump out subsurface sulphur) or as a byproduct of petrochemical refining, where it is removed to prevent equipment corrosion. Another, more ancient method is what is denominated the Sicilian process, which consists of burning the ores in a pile and collecting the residual sulphur, but this method is largely obsolete in the modern age. Sulphur itself has limited direct applications, since its primary importance is as the feedstock for the production of Chemicals (Sulphuric Acid), the most widely produced industrial chemical in the world. Secondary direct uses include vulcanisation of rubber, fungicides, and black powder manufacture. The Frasch process, where applicable, is among the simpler large-scale mineral recovery operations.