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==Occurrence and mining==
[[File:Closeup of Fluorite.jpg|thumb|A closeup of fluorite surface|alt=black, chevronned (wavy, jagged) structure]]
[[File:Fluorite-146260.jpg|thumb|Blue Fluorite, from Shihe District, [[Henan Province]], China ]]
Fluorite forms as a late-crystallizing mineral in [[felsic]] [[igneous]] rocks typically through hydrothermal activity.<ref name="Deer 2013 p. ">{{cite book | last=Deer | first=W. A. | title=An introduction to the rock-forming minerals | publisher=The Mineralogical Society | location=London | year=2013 | isbn=978-0-903056-27-4 | oclc=858884283 }}</ref> It is particularly common in granitic pegmatites. It may occur as a [[Vein (geology)|vein deposit]] formed through [[hydrothermal]] activity particularly in limestones. In such vein deposits it can be associated with [[galena]], [[sphalerite]], [[barite]], [[quartz]], and [[calcite]]. Fluorite can also be found as a constituent of sedimentary rocks either as grains or as the cementing material in [[sandstone]].<ref name="Deer 2013 p. "/>

It is a common mineral mainly distributed in South Africa, China, Mexico, Mongolia, the United Kingdom, the United States, Canada, Tanzania, Rwanda and Argentina.

The world reserves of fluorite are estimated at 230 million [[tonne]]s (Mt) with the largest deposits being in [[South Africa]] (about 41 Mt), Mexico (32 Mt) and China (24 Mt). China is leading the world production with about 3 Mt annually (in 2010), followed by Mexico (1.0 Mt), [[Mongolia]] (0.45 Mt), [[Russia]] (0.22 Mt), South Africa (0.13 Mt), Spain (0.12 Mt) and Namibia (0.11 Mt).<ref>[https://minerals.usgs.gov/minerals/pubs/commodity/fluorspar/mcs-2011-fluor.pdf Fluorspar]. USGS.gov (2011)</ref>{{Update inline|reason=Says, in 2010, China had 24 Mt and was mining 3 Mt annually, so now should have none|date=December 2019}}

One of the largest deposits of fluorspar in North America is located on the [[Burin Peninsula]], [[Newfoundland (island)|Newfoundland]], Canada. The first official recognition of fluorspar in the area was recorded by geologist J.B. Jukes in 1843. He noted an occurrence of "galena" or lead ore and fluoride of lime on the west side of St. Lawrence harbour. It is recorded that interest in the commercial mining of fluorspar began in 1928 with the first ore being extracted in 1933. Eventually, at Iron Springs Mine, the shafts reached depths of {{convert|970|ft|m}}. In the St. Lawrence area, the veins are persistent for great lengths and several of them have wide [[Lens (geology)|lenses]]. The area with veins of known workable size comprises about {{convert|60|sqmi|km2}}.<ref>[https://web.archive.org/web/20110708113037/http://www.canadafluorspar.com/BML_Proj_Registration_Master.pdf Reactivation of the St. Lawrence fluorspar mine at St. Lawrence, NL]. Burin Minerals Ltd. (April 9, 2009).</ref><ref>{{cite journal|last1=Van Alstine|first1=R. E.|title=The fluorspar deposits of Saint Lawrence, Newfoundland|journal=Economic Geology|volume=39|page=109|year=1944|doi=10.2113/gsecongeo.39.2.109|issue=2|bibcode=1944EcGeo..39..109V }}</ref><ref>{{cite journal|last1=Strong|first1=D. F.|last2=Fryer|first2=B. J.|last3=Kerrich|first3=R.|title=Genesis of the St. Lawrence fluorspar deposits as indicated by fluid inclusion, rare earth element, and isotopic data|journal=Economic Geology|volume=79|page=1142|year=1984|doi=10.2113/gsecongeo.79.5.1142|issue=5|bibcode=1984EcGeo..79.1142S }}</ref>

In 2018, Canada Fluorspar Inc. commenced mine production again<ref>{{cite web|url=https://www.cbc.ca/news/canada/newfoundland-labrador/fluorspar-mine-investment-st-lawrence-1.4026074|title=St. Lawrence fluorspar mine gets $5M from feds, hundreds of jobs touted|website=Cbc.ca|access-date=14 December 2021}}</ref> in St. Lawrence; in spring 2019, the company was planned to develop a new shipping port on the west side of Burin Peninsula as a more affordable means of moving their product to markets,<ref>{{Cite web|url=https://www.saltwire.com/newfoundland-labrador/news/local/cfi-seeking-new-location-for-shipping-port-in-st-lawrence-nl-305947/|title=CFI seeking new location for shipping port in St. Lawrence, NL &#124; SaltWire|first=Colin|last=Farrell|website=Saltwire.com|access-date=14 December 2021}}</ref> and they successfully sent the first shipload of ore from the new port on July 31, 2021. This marks the first time in 30 years that ore has been shipped directly out of St. Lawrence.<ref>{{Cite web|url=https://vocm.com/2021/07/31/first-shipment-of-fluorspar-in-over-30-years-exported-from-st-lawrence/|title=First Shipment of Fluorspar in Over 30 Years Exported From St. Lawrence|first=Noah|last=Sheppard|website=Vocm.com|access-date=14 December 2021}}</ref>

Cubic crystals up to 20&nbsp;cm across have been found at [[Dalnegorsk]], Russia.<ref>Korbel, P. and Novak, M. (2002) ''The Complete Encyclopedia of Minerals'', Book Sales, {{ISBN|0785815201}}.</ref> The largest documented single crystal of fluorite was a cube 2.12 meters in size and weighing approximately 16 tonnes.<ref>{{cite journal |url=http://www.minsocam.org/ammin/AM66/AM66_885.pdf |archive-url=https://web.archive.org/web/20090620081033/http://www.minsocam.org/ammin/AM66/AM66_885.pdf |archive-date=2009-06-20 |url-status=live|journal=American Mineralogist|volume=66|pages=885–907|year=1981|title=The largest crystals|author=Rickwood, P. C.}}</ref>  
[[File:Barite-Fluorite-fluoritespain.jpg|thumb|Fluorite on barite from the Berbes mine, Ribadesella, Asturias (Spain).  Fluorite crystal, 2.2 cm.]]
In [[Asturias]] ([[Spain]]) there are several fluorite deposits known internationally for the quality of the specimens they have yielded. In the area of [[Berbes]], [[Ribadesella]], fluorite appears as cubic crystals, sometimes with dodecahedron modifications, which can reach a size of up to 10&nbsp;cm of edge, with internal colour zoning, almost always violet in colour. It is associated with quartz and leafy aggregates of baryte. In the ''Emilio'' mine, in Loroñe, [[Colunga]], the fluorite crystals, cubes with small modifications of other figures, are colourless and transparent. They can reach 10&nbsp;cm of edge. In the ''Moscona'' mine, in Villabona, the fluorite crystals, cubic without modifications of other shapes, are yellow, up to 3&nbsp;cm of edge. They are associated with large crystals of calcite and barite.<ref>{{Cite book |last1=Calvo Sevillano |first1=Guiomar |title=Fluorite. The Collector's Choice |last2=Calvo Rebollar |first2=Miguel |publisher=Lithographie LLC. Connecticut, USA |year=2006 |location=Connecticut, USA |pages=38–42 |chapter=Fluorite from Spain. Every color under the Sun}}</ref>

==="Blue John"===<!-- This section is linked from [[Peak District]] -->
{{Main|Blue John (mineral)}}
One of the most famous of the older-known localities of fluorite is [[Castleton, Derbyshire|Castleton]] in [[Derbyshire]], [[England]], where, under the name of "Derbyshire Blue John", purple-blue fluorite was extracted from several mines or caves. During the 19th century, this attractive fluorite was mined for its ornamental value. The mineral Blue John is now scarce, and only a few hundred kilograms are mined each year for ornamental and [[lapidary]] use. Mining still takes place in [[Blue John Cavern]] and [[Treak Cliff Cavern]].<ref>{{cite book|title=Chemistry in context|author1=Hill, Graham  |author2=Holman, John |year=2000|isbn=0174482760|publisher=Nelson Thornes}}</ref>

Recently discovered deposits in China have produced fluorite with coloring and banding similar to the classic Blue John stone.<ref>{{cite journal|last1=Ford|first1=Trevor D.|title=Blue John fluorspar|journal=Geology Today|volume=10|page=186|year=1994|doi=10.1111/j.1365-2451.1994.tb00422.x|issue=5|bibcode=1994GeolT..10..186F }}</ref>