Fluorite
Cubic fluorite crystals from Blue John Cavern
General
Category	mineral
Chemical formula	calcium fluoride CaF2
Identification
Color	Colorless, white, purple, blue, blue-green, green, yellow, brownish-yellow, pink or red
Crystal habit	Occurs as well-formed coarse sized crystals also massive - granular
Crystal system	Isometric 4/m bar 3 2/m
Cleavage	[111] Perfect, [111] Perfect, [111] Perfect
Fracture	Uneven
Mohs Scale hardness	4
Luster	Vitreous
Refractive index	1.433–1.435
Streak	White
Specific gravity	3.18
Fusibility	3
Solubility	Slightly in water
Other Characteristics	sometimes phosphoresces when heated or scratched. Other varieties fluoresce

Fluorite (also called fluorspar) is a mineral composed of calcium fluoride, CaF₂. It is an isometric mineral with a cubic habit, though octahedral and more complex isometric forms are not uncommon. Cubic crystals up to 20 cm across have been found at Dalnegorsk, Russia.^[1] Crystal twinning is common and adds complexity to the observed crystal habits. Image File history File links Metadata Size of this preview: 682 × 600 pixelsFull resolution (2374 × 2088 pixel, file size: 2. ... Entrance to the Blue John cavern The Blue John Cavern is one of the four show caves in Castleton, Derbyshire, England. ... A chemical formula is a concise way of expressing information about the atoms that constitute a particular chemical compound. ... For other uses, see Calcium (disambiguation). ... Fluoride is the ionic form of fluorine. ... In mineralogy, shape and size give rise to descriptive terms applied to the typical appearance, or habit of crystals. ... A crystal system is a category of space groups, which characterize symmetry of structures in three dimensions with translational symmetry in three directions, having a discrete class of point groups. ... In crystallography, the cubic crystal system (or isometric crystal system) is the most symmetric of the 7 crystal systems. ... Cleavage, in mineralogy, is the tendency of crystalline materials to split along definite planes, creating smooth surfaces, of which there are several named types: Basal cleavage: cleavage parallel to the base of a crystal, or to the plane of the lateral axes. ... For other uses, see Fracture (disambiguation). ... Mohs scale of mineral hardness characterizes the scratch resistance of various minerals through the ability of a harder material to scratch a softer. ... Lustre (American English: luster) is a description of the way light interacts with the surface of a crystal, rock or mineral. ... The refractive index (or index of refraction) of a medium is a measure for how much the speed of light (or other waves such as sound waves) is reduced inside the medium. ... The streak (also called powder color) of a mineral is the color of the powder produced when it is dragged across a unweathered surface. ... Relative density (also known as specific gravity) is a measure of the density of a material. ... Fusibility is the ease with which a material will melt. ... Solubility is a chemical property referring to the ability for a given substance, the solute, to dissolve in a solvent. ... In common use, phosphorescence also refers to the emission of light by bioluminescent plankton, and some other forms of chemoluminescence. ... Fluorescence induced by exposure to ultraviolet light in vials containing various sized Cadmium selenide (CdSe) quantum dots. ... For other uses, see Mineral (disambiguation). ... Calcium fluoride (CaF2) is an insoluble ionic compound of calcium and fluorine. ... For other uses, see Calcium (disambiguation). ... Distinguished from fluorene and fluorone. ... In crystallography, the cubic crystal system (or isometric crystal system) is the most symmetric of the 7 crystal systems. ... It has been suggested that twin boundary be merged into this article or section. ... For other uses, see Crystal (disambiguation). ...

The word fluorite is derived from the Latin root fluo, meaning "to flow" because the mineral has a relatively low melting point and was used as an important flux in smelting. Fluorite gave its name to its constitutive element fluorine. For other uses, see Latins and Latin (disambiguation). ... flux in science and mathematics. ... Distinguished from fluorene and fluorone. ...

Occurrence

Fluorite may occur as a vein deposit, especially with metallic minerals, where it often forms a part of the gangue (the worthless "host-rock" in which valuable minerals occur) and may be associated with galena, sphalerite, barite, quartz, and calcite. It is a common mineral in deposits of hydrothermal origin and has been noted as a primary mineral in granites and other igneous rocks and as a common minor constituent of dolostone and limestone. Tailings, also called gangue, are the rejected material from mining and screening operations. ... For other uses, see Galena (disambiguation). ... Sphalerite sample Another sphalerite sample The unit cell of sphalerite Sphalerite (ZnS) is a gay mineral that is the chief ore of zinc. ... Baryte with Cerussite from Morocco Baryte with Galena and Hematite from Poland Barite (BaSO4) is a mineral consisting of barium sulfate. ... For other uses, see Quartz (disambiguation). ... Doubly refracting Calcite from Iceberg claim, Dixon, New Mexico. ... Hydrothermal circulation in the oceans is the passage of the water through mid-ocean Ridge (MOR) systems. ... For other uses, see granite (disambiguation). ... Igneous rocks (etymology from Latin ignis, fire) are rocks formed by solidification of cooled magma (molten rock), with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks. ... Dolostone is a sedimentary carbonate rock that contains a high percentage of the mineral dolomite. ... For other uses, see Limestone (disambiguation). ...

Fluorite is a widely occurring mineral which is found in large deposits in many areas. Notable deposits occur in Germany, Austria, Switzerland, England, Norway, Mexico, and Ontario in Canada. Large deposits also occur in Kenya in the Kerio Valley area within the Great Rift Valley. In the United States deposits are found in Missouri, Oklahoma, Illinois, Kentucky, Colorado, New Mexico, Arizona, Ohio, New Hampshire, New York, Alaska and Texas. Illinois has historically been the largest producer of fluorite in the United States, however, the last of the mines closed in 1995. The Illinois general assembly passed a resolution in 1965 declaring fluorite as the official state mineral. For other uses, see England (disambiguation). ... Motto: Ut Incepit Fidelis Sic Permanet (Latin: Loyal she began, loyal she remains) Capital Toronto Largest city Toronto Official languages English (de facto) Government Lieutenant-Governor David C. Onley Premier Dalton McGuinty (Liberal) Federal representation in Canadian Parliament House seats 107 Senate seats 24 Confederation July 1, 1867 (1st) Area... This article is about the U.S. state. ... For other uses, see Oklahoma (disambiguation). ... Official language(s) English[1] Capital Springfield Largest city Chicago Largest metro area Chicago Metropolitan Area Area  Ranked 25th  - Total 57,918 sq mi (140,998 km²)  - Width 210 miles (340 km)  - Length 390 miles (629 km)  - % water 4. ... Official language(s) English[1] Capital Frankfort Largest city Louisville Area  Ranked 37th  - Total 40,444 sq mi (104,749 km²)  - Width 140 miles (225 km)  - Length 379 miles (610 km)  - % water 1. ... Official language(s) English Capital Denver Largest city Denver Largest metro area Denver-Aurora Metro Area Area  Ranked 8th  - Total 104,185 sq mi (269,837 km²)  - Width 280 miles (451 km)  - Length 380 miles (612 km)  - % water 0. ... Capital Santa Fe Largest city Albuquerque Largest metro area Albuquerque metropolitan area Area  Ranked 5th  - Total 121,665 sq mi (315,194 km²)  - Width 342 miles (550 km)  - Length 370 miles (595 km)  - % water 0. ... Official language(s) English Spoken language(s) English 74. ... This article is about the U.S. State. ... For other uses, see New Hampshire (disambiguation). ... This article is about the state. ... For other uses, see Alaska (disambiguation). ... For other uses, see Texas (disambiguation). ... Official language(s) English[1] Capital Springfield Largest city Chicago Largest metro area Chicago Metropolitan Area Area  Ranked 25th  - Total 57,918 sq mi (140,998 km²)  - Width 210 miles (340 km)  - Length 390 miles (629 km)  - % water 4. ...

Blue John

Vein of Blue John in Treak Cliff Cavern

One of the most famous of the older-known localities of fluorite is Castleton in Derbyshire, England, where, under the name of Derbyshire Blue John, purple-blue fluorite was extracted from several mines/caves, including the famous Blue John Cavern. During the 19th century, this attractive fluorite was mined for its ornamental value. The name derives from French "bleu et jaune" (blue and yellow) characterising its color. 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 the nearby Treak Cliff Cavern. Recent deposits in China have produced fluorite with coloring and banding similar to the classic Blue John stone. This article is about the English village. ... Derbyshire is a county in the East Midlands of England. ... For other uses, see England (disambiguation). ... Entrance to the Blue John cavern The Blue John Cavern is one of the four show caves in Castleton, Derbyshire, England. ... Kg redirects here. ... A lapidary (the word means concerned with stones) is an artisan who practices the craft of working, forming and finishing stone, mineral, gemstones, and other suitably durable materials (amber, shell, jet, pearl, copal, coral, horn and bone, glass and other synthetics) into functional and/or decorative, even wearable, items (e. ...

Fluorescence

Yellow fluorite (~ 4 cm in height)

Many samples of fluorite fluoresce under ultra-violet light, a property that takes its name from fluorite. Many minerals, as well as other substances, fluoresce. Fluorescence involves the elevation of electron energy levels by quanta of ultra-violet light, followed by the progressive falling back of the electrons into their previous energy state, releasing quanta of visible light in the process. In fluorite, the visible light emitted is most commonly blue, but red, purple, yellow, green and white also occur. The fluorescence of fluorite may be due to impurities such as yttrium or organic matter in the crystal lattice. It is not surprising, therefore, that the color of visible light emitted when a sample of fluorite is fluorescing appears dependent on where the original specimen was collected, different impurities having been included in the crystal lattice in different places. Neither do all fluorites fluoresce equally brightly, even from the same locality. Therefore ultra-violet light is not a reliable tool for the identification of specimens, nor for quantifying the mineral in mixtures. For example, among British fluorites, those from Northumberland, County Durham and Eastern Cumbria are the most consistently fluorescent, whereas fluorites from Yorkshire, Derbyshire and Cornwall, if they fluoresce at all, are generally only feebly fluorescent. Fluorescence induced by exposure to ultraviolet light in vials containing various sized Cadmium selenide (CdSe) quantum dots. ... Note: Ultraviolet is also the name of a 1998 UK television miniseries about vampires. ... Fluorescence induced by exposure to ultraviolet light in vials containing various sized Cadmium selenide (CdSe) quantum dots. ... Note: Ultraviolet is also the name of a 1998 UK television miniseries about vampires. ... Fluorescence induced by exposure to ultraviolet light in vials containing various sized Cadmium selenide (CdSe) quantum dots. ... General Name, Symbol, Number yttrium, Y, 39 Chemical series transition metals Group, Period, Block 3, 5, d Appearance silvery white Standard atomic weight 88. ... Note: Ultraviolet is also the name of a 1998 UK television miniseries about vampires. ... Northumberland is a county in the North East of England. ... County Durham is a county in north-east England. ... Cumbria (IPA: ), is a shire county in the extreme North West of England. ... Yorkshire is a historic county of northern England. ... Derbyshire is a county in the East Midlands of England. ... For other uses, see Cornwall (disambiguation). ...

Fluorite also exhibits the property of thermoluminescence. Some mineral substances such as fluorite store energy when exposed to ultraviolet or other ionising radiation. ...

Uses

Deep purple cubes of fluorite with galena (gray) and calcite (white) from Illinois, USA

There are three principal types of industrial use for fluorite, corresponding to different grades of purity. Metallurgical grade fluorite, the lowest of the three grades, has traditionally been used as a flux to lower the melting point of raw materials in steel production to aid the removal of impurities, and later in the production of aluminium. Ceramic (intermediate) grade fluorite is used in the manufacture of opalescent glass, enamels and cooking utensils. The highest grade, acid grade fluorite, is used to make hydrofluoric acid by decomposing the fluorite with sulfuric acid. Hydrofluoric acid is the primary feedstock for the manufacture of virtually all organic and inorganic fluorine-containing compounds, including fluoropolymers and perfluorocarbons, and is also used to etch glass. Image File history File links Size of this preview: 713 × 600 pixelsFull resolution (1372 × 1154 pixels, file size: 344 KB, MIME type: image/jpeg) (All user names refer to en. ... Image File history File links Size of this preview: 713 × 600 pixelsFull resolution (1372 × 1154 pixels, file size: 344 KB, MIME type: image/jpeg) (All user names refer to en. ... In metallurgy, flux is a substance which removes passivating oxides from the surface of a metal or alloy. ... For other uses, see Steel (disambiguation). ... Aluminum redirects here. ... OPAL is also the name of one of the four detectors of the Large Electron-Positron Collider. ... This article is about the material. ... In a discussion of art technology, enamel (or vitreous enamel, or porcelain enamel in American English) is the colorful result of fusion of powdered glass to a substrate through the process of firing, usually between 750 and 850 degrees Celsius. ... R-phrases , S-phrases , , , , Flash point nonflammable Related Compounds Other anions Hydrochloric acid Hydrobromic acid Hydroiodic acid Related compounds Hydrogen fluoride fluorosilicic acid Supplementary data page Structure and properties n, εr, etc. ... R-phrases S-phrases , , , Flash point Non-flammable Related Compounds Related strong acids Selenic acid Hydrochloric acid Nitric acid Related compounds Hydrogen sulfide Sulfurous acid Peroxymonosulfuric acid Sulfur trioxide Oleum Supplementary data page Structure and properties n, εr, etc. ... A fluoropolymer is a polymer that contains atoms of fluorine. ... Fluorotelomer alcohol FTOH 8:2 Perfluorocarbons (PFCs) are compounds derived from hydrocarbons by replacement of hydrogen atoms by fluorine atoms. ...

Fluorite is used instead of glass in some high performance telescopes and camera lens elements. Exposure tools for the semiconductor industry make use of fluorite optical elements for ultraviolet light at 157 nm wavelength. Fluorite has a uniquely high transparency at this wavelength. Fluorite has a very low dispersion so lenses made from it exhibit less chromatic aberration than those made of ordinary glass. In telescopes it allows crisp images of astronomical objects even at high power. Fluorite also has ornamental and lapidary uses. The Canon camera company produces synthetic fluorite crystals which are used in their more expensive telephoto lenses. Eight Inch refracting telescope. ... A photographic lens (or more correctly, objective) is an integrated system comprising one or more simple optical lens elements, used for a camera or microscope. ... A semiconductor is a solid whose electrical conductivity is in between that of a conductor and that of an insulator, and can be controlled over a wide range, either permanently or dynamically. ... Note: Ultraviolet is also the name of a 1998 UK television miniseries about vampires. ... For other uses, see Wavelength (disambiguation). ... Dispersion of a light beam in a prism. ... On top is corner detail in a photograph taken with a higher quality lens; bottom is a similar photograph taken with a wide angle lens showing visible chromatic aberration (especially at the dark edges on the right). ... Optical power or dioptric power or refractive power is the degree to which a lens or mirror converges or diverges light. ... A lapidary (the word means concerned with stones) is an artisan who practices the craft of working, forming and finishing stone, mineral, gemstones, and other suitably durable materials (amber, shell, jet, pearl, copal, coral, horn and bone, glass and other synthetics) into functional and/or decorative, even wearable, items (e. ...

Gallery

Pig carved in fluorite, 5 cm (2 inches) long This is a file from the Wikimedia Commons, a repository of free content hosted by the Wikimedia Foundation. ...	Mineral fluorite Image File history File links Mineral Fluorite USDA Photo by: Ken Hammond USDA Image Number: 93cs3962 Source: http://www. ...	Octahedral fluorite crystals from New Mexico, USA Commons:Image:Fluorite USA.jpg File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...	Cleaved fluorite octahedra Commons:Imagem:Fluorite_crystals_270x444. ...
The unit cell of fluorite's crystal structure Image File history File links Size of this preview: 591 × 600 pixelsFull resolution (1084 × 1100 pixels, file size: 351 KB, MIME type: image/png) File historyClick on a date/time to view the file as it appeared at that time. ...

Commons:Imagem:Fluorite China. ...

See also

• List of minerals

Gem animals. ...

References

• Hurlbut, Cornelius S.; Klein, Cornelis, 1985, Manual of Mineralogy, pp. 324 - 325, 20th ed., ISBN 0-471-80580-7
• Mineral Galleries
• Webmineral
• Mindat.org
• Fluorspar

1. ^ The Complete Encyclopedia of Minerals by P. Korbel and M. Novak

Image File history File links Commons-logo. ...

External links

• an educational tour of Weardale Fluorite
• Illinois State Geologic Survey
• Illinois state mineral
• Barber Cup and Crawford Cup, related Roman cups at British Museum.
• Fluorites and antifluorites at NCSU
• Spanish Fluorite