Fluorine is the thirteenth most common element in Earth's crust at 600–700 ppm (parts per million) by mass.
Elemental fluorine does not occur naturally.
Instead, all fluorine exists as fluoride-containing minerals.
Fluorite, fluorapatite and cryolite are the most industrially significant.
Fluorite, also known as fluorspar, (CaF
₂), abundant worldwide, is the main source of fluoride, and hence fluorine.
China and Mexico are the major suppliers.
Fluorapatite (Ca₅(PO₄)₃F), which contains most of the world's fluoride, is an inadvertent source of fluoride as a byproduct of fertilizer production.
Cryolite (Na
₃AlF
₆), used in the production aluminium, is the most fluorine-rich mineral.
Economically viable natural sources of cryolite have been exhausted, and most is now synthesised commercially.

Other minerals such as topaz contain fluorine.
Fluorides, unlike other halides, are insoluble and do not occur in commercially favorable concentrations in saline waters.
Trace quantities of organofluorines of uncertain origin have been detected in volcanic eruptions and geothermal springs.
The existence of gaseous fluorine in crystals, suggested by the smell of crushed antozonite, is contentious; a 2012 study reported the presence of 0.04% F
₂ by weight in antozonite, attributing these inclusions to radiation from the presence of tiny amounts of uranium.
Fluorine is the thirteenth most common element in Earth's crust at 600–700 ppm (parts per million) by mass. Elemental fluorine does not occur naturally. Instead, all fluorine exists as fluoride-containing minerals. Fluorite, fluorapatite and cryolite are the most industrially significant. Fluorite, also known as fluorspar, (CaF
₂), abundant worldwide, is the main source of fluoride, and hence fluorine. China and Mexico are the major suppliers. Fluorapatite (Ca₅(PO₄)₃F), which contains most of the world's fluoride, is an inadvertent source of fluoride as a byproduct of fertilizer production. Cryolite (Na
₃AlF
₆), used in the production aluminium, is the most fluorine-rich mineral. Economically viable natural sources of cryolite have been exhausted, and most is now synthesised commercially.
Other minerals such as topaz contain fluorine. Fluorides, unlike other halides, are insoluble and do not occur in commercially favorable concentrations in saline waters. Trace quantities of organofluorines of uncertain origin have been detected in volcanic eruptions and geothermal springs. The existence of gaseous fluorine in crystals, suggested by the smell of crushed antozonite, is contentious; a 2012 study reported the presence of 0.04% F
₂ by weight in antozonite, attributing these inclusions to radiation from the presence of tiny amounts of uranium.
Fluorine