SULPHUR Native sulphur, or brimstone, occurs in many places throughout the world, generally either in beds of gypsum, limestone and associated rocks or in the vicinity of active and extinct volcanoes. The principal extensive deposits are found along the Gulf coastal plain of the United States, in two places in Sicily, at several points on the mainland of Italy, in Japan, Spain, Austria, in the Aleu tian islands, Alaska, in the Chilean Andes, South America, in China, India, Russia and in several of the South Sea islands. Until 1905, Sicily controlled the sulphur industry, approximately 85% of the total world's supply being produced in Sicily and Italy.
It was discovered many years ago when drilling for oil that sulphur existed in large quantities in the saline dome formations of the Gulf coastal plain of the U.S. No successful method was devised for winning this sulphur until the development of the Frasch process about 1900. (See SULPHUR.) With sulphur obtained at low cost by this process, the deposits of Louisiana and Texas became the principal sources for the world, the Sicilian production taking second place. Since 1934 about
78% of the world's supply has been from the Gulf coast field, 13% from Sicily, 6% from Japan, and 3% from other countries.
No recent data are available on the reserves of any of the lead ing producers, but it is known that they are sufficient to supply the demand for many years, although the current world consump tion has grown to some 3,000,c:0o-3,500,00o tons annually. New discoveries are still being made, and moderately extensive deposits are known in other parts of the United States which are not yet commercially profitable. Pyrite ores and waste smelter gases yield considerable amounts of sulphur which supplement the supply of native sulphur.
The chief use for native sulphur is to burn it to sulphur dioxide gas for the manufacture of sulphuric acid or for the production of sulphite liquors for paper pulp manufacture. For certain chemical purposes, especially for the production of agricultural insecticide sprays, and in the manufacture of rubber and sulphuretted prod ucts, native sulphur has a distinct field of use. (A. E. W.; X.)