Sulfur vulcanization a reaction with low levels of unsaturated organic linkers (e.g. 1,3‐diisopropenylbenzene). This process is called inverse vulcanisation and produces polymers where sulfur is the main component. It is not currently of commercial importance but had been investigated as a means of producing polymers for lithium–sulfur batterys and for creating water filters with a high affinity for mercury. The curing of rubber has been carried out since prehistoric times. The name of the first major civilization in Guatemala and Mexico, the Olmec, means 'rubber people' in the Aztec language. Ancient Mesoamericans, spanning from ancient Olmecs to Aztecs, extracted latex from "Castilla
Frasch process 1894, when the first molten sulfur was brought to the surface. The Union Sulphur Company was incorporated in 1896 to utilize the process. However, the high cost of fuel needed to heat the water made the process uneconomic until the 1901 discovery of the Spindletop oil field in Texas provided cheap fuel oil to the region. The Frasch process began economic production at Sulphur Mines, Louisiana in 1903. When Frasch's patent expired, the process was widely applied to similar salt-dome sulfur deposits along the Gulf Coast of the United States. The second Frasch-process mine opened in 1912 in Brazoria County,