There are three principal types of industrial use for natural fluorite, commonly referre
as "fluorspar" in these industries, corresponding to different grades of purity.
Metallurgical grade fluorite (60–85% CaF2), the lowest of the three grades, has
traditionally been used as a flux to lower the melting point of raw materials in steel
production to aid the removal of impurities, and later in the production of aluminum.
Ceramic grade fluorite (85–95% CaF2) is used in the manufacture of opalescent glass,
enamels and cooking utensils.
The highest grade, "acid grade fluorite" (97% or higher purity), accounts for about 95%
of fluorite consumption in the US where it is used to make hydrogen fluoride and
hydrofluoric acid by reacting the fluorite with sulfuric acid.