Fluorite

Fluorite is the mineral form of calcium fluoride, CaF₂.

 1. 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 aluminium.

2.Ceramic grade fluorite (85–95% CaF₂), is used in the manufacture of opalescent glass, enamels, and cooking utensils

3.The highest grade, "acid grade fluorite" (97% or more CaF₂), 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.