Agricola derived the name fluores from fluo "to flow," and we in turn obtain "fluorite," or "fluorspar," from Agricola.
Only certain varieties of fluorite show the phenomenon well.
Some specimens of fluorite (CaF2) show the phenomenon especially well, whence the name fluorescence.
Rays passing through the fluorite window strike the blackened side of the mica, which is parallel and opposite to it.
In England, fluorite is obtained in this manner as a by-product from lead and zinc mines.
fluorite is widely distributed, most commonly in vein deposits, often associated with metallic ores.
Some fissure veins of fluorite in limestone in southern Illinois are twenty to forty feet wide.
A transparent to translucent mineral occurring in many colors, especially yellow and purple, and usually in cube-shaped crystals with octahedral cleavage. It is found in sedimentary rocks and in ore deposits within igneous rocks. It is often fluorescent in ultraviolet light. Chemical formula: CaF2.