Fluorite
Fluorite is the mineral form of calcium fluoride. It has a chemical formula of CaF
2.
Fluorite is the main source of fluorine and fluorides. It naturally fluoridates drinking water in places where it is found. It has a hardness of 5. It barely dissolves in water. Geologists have found about 9000 deposits of fluorite found on the Earth. It is mainly mined in China, Mexico and Russia.
Fluorite Media
Blue Fluorite, from Shihe District, Henan Province, China
Fluorescing fluorite from Boltsburn Mine, Weardale, North Pennines, County Durham, England, UK.
Crawford Cup (Roman, 50-100 CE) in the collection of the British Museum. Made of fluorite.