... In 1852 fluorite gave its name to the phenomenon of fluorescence, which is prominent in fluorites from certain locations, due ... natural fluorite, corresponding to different grades of purity. Metallurgical grade fluorite, the lowest of the three grades, has traditionally ... of opalescent glass, enamels and cooking utensils. The highest grade, "acid grade fluorite" (97% or more CaF2), is used to ...