78,000 Industrias Quimicas, San Luis Potosi, Mex.
Production is by reaction of acid-grade fluorspar with sulfuric acid in a furnace.
AlliedSignal reopened its Amherstburg plant in late 1996. Idled since 1992, the plant's equipment has been tested and one train is running. Plans call for production to be stepped up gradually, with both furnaces in operation by the end of the year as demand warrants. Allied also has a 49 percent share in Quimbasicos. Elf Atochem mothballed its 28,000-ton Calvert City, Ky., HF plant in February 1996.