Editing Quartzite

{{Short description|Hard, non-foliated metamorphic rock}}
{{For|the similarly-named town|Quartzsite, Arizona}}{{Infobox rock|name=Quartzite|type=Metamorphic|caption=Quartzite, containing darker bands of phengite and chlorite, from Maurienne Valley in the [[French Alps]]|composition=Quartz|regoliths=|image=Quartzite Sollières.jpg|protolith=Quartz [[Sandstone]]|fabric=Non-foliated}}[[File:Sample of Quartzite.JPG|thumb|Quartzite can have a grainy, glassy, sandpaper-like surface]]

'''Quartzite''' is a hard, non-[[Foliation (geology)|foliated]] [[metamorphic rock]] that was originally pure [[quartz]] [[sandstone]].<ref name= EG>Essentials of Geology, 3rd Edition, Stephen Marshak, p 182</ref><ref name="MII">{{cite web|url=http://www.mii.org/Minerals/photoquartzite.html|title=Quartzite|last=Powell|first=Darryl|publisher=Mineral Information Institute|access-date=2009-09-09|url-status=dead|archive-url=https://web.archive.org/web/20090302072709/http://www.mii.org/Minerals/photoquartzite.html|archive-date=2009-03-02}}</ref> Sandstone is converted into quartzite through heating and pressure usually related to [[tectonics|tectonic]] compression within [[orogeny|orogenic belts]], and hence quartzite is a metasandstone. Pure quartzite is usually white to grey, though quartzites often occur in various shades of pink and red due to varying amounts of [[hematite]]. Other colors, such as yellow, green, blue  and orange, are due to other minerals.

The term ''quartzite'' is also sometimes used for very hard but unmetamorphosed [[sandstones]] that are composed of quartz grains thoroughly cemented with additional quartz. Such sedimentary rock has come to be described as '''orthoquartzite''' to distinguish it from metamorphic quartzite, which is sometimes called '''metaquartzite''' to emphasize its metamorphic origins.<ref name=jackson1997>{{cite book |editor1-last=Jackson |editor1-first=Julia A. |title=Glossary of geology. |date=1997 |publisher=American Geological Institute |location=Alexandria, Virginia |isbn=0922152349 |edition=Fourth |page=525}}</ref><ref name=oxford2013>{{cite book |last1=Allaby |first1=Michael |title=A dictionary of geology and earth sciences |date=2013 |publisher=Oxford University Press |location=Oxford |isbn=9780199653065 |edition=Fourth}}</ref>

Quartzite is very resistant to chemical [[weathering]] and often forms ridges and resistant hilltops. The nearly pure silica content of the rock provides little material for [[soil]]; therefore, the quartzite ridges are often bare or covered only with a very thin layer of soil and little (if any) vegetation. Some quartzites contain just enough weather-susceptible nutrient-bearing minerals such as [[carbonates]] and [[Chlorite group|chlorite]] to form a loamy, fairly fertile though shallow and stony soil.

Quartzite has been used since prehistoric times for stone tools. It is presently used for decorative dimension stone, as crushed stone in highway construction, and as a source of [[silica]] for production of [[silicon]] and silicon compounds.

==Characteristics and origin==
Quartzite is a very hard rock composed predominantly of an interlocking mosaic of quartz crystals. The grainy, sandpaper-like surface is glassy in appearance. Minor amounts of former cementing materials, iron oxide, silica, carbonate and clay, often migrate during recrystallization, causing streaks and lenses to form within the quartzite.<ref name= EG/> To be classified as a quartzite by the [[British Geological Survey]], a metamorphic rock must contain at least 80% quartz by volume.<ref name="BGS">{{cite journal |last1=Robertson |first1=S. |title=BGS Rock Classification Scheme, Volume 2: Classification of metamorphic rocks |journal=British Geological Survey Research Report |date=1999 |volume=RR 99-02 |url=http://nora.nerc.ac.uk/id/eprint/3226/1/RR99002.pdf |access-date=27 February 2021}}</ref>

Quartzite is commonly regarded as metamorphic in origin.<ref name=BlattTracy1996>{{cite book |last1=Blatt |first1=Harvey |last2=Tracy |first2=Robert J. |title=Petrology : igneous, sedimentary, and metamorphic. |date=1996 |publisher=W.H. Freeman |location=New York |isbn=0716724383 |edition=2nd |page=367}}</ref><ref name=oxford2013/> When sandstone is subjected to the great heat and pressure associated with regional metamorphism, the individual quartz grains recrystallize along with the former cementing material. Most or all of the original texture and sedimentary structures of the sandstone are erased by the metamorphism.<ref name= EG/> The recrystallized quartz grains are roughly equal in size, forming what is called a granoblastic texture, and they also show signs of metamorphic annealing, in which the grains become coarser and acquire a more polygonal texture.<ref name=BlattTracy1996/> The grains are so tightly interlocked that when the rock is broken, it fractures through the grains to form an  irregular or conchoidal fracture.<ref name=Howard2005>{{cite journal |last1=Howard |first1=Jeffrey L. |title=The Quartzite Problem Revisited |journal=The Journal of Geology |date=November 2005 |volume=113 |issue=6 |pages=707–713 |doi=10.1086/449328|bibcode=2005JG....113..707H |s2cid=128463511 |url=https://digitalcommons.wayne.edu/cgi/viewcontent.cgi?article=1077&context=geofrp |url-access=subscription }}</ref>

Geologists had recognized by 1941 that some rocks show the macroscopic characteristics of quartzite, even though they have not undergone metamorphism at high pressure and temperature. These rocks have been subject only to the much lower temperatures and pressures associated with [[diagenesis]] of sedimentary rock, but diagenesis has cemented the rock so thoroughly that microscopic examination is necessary to distinguish it from metamorphic quartize. The term ''orthoquartzite'' is used to distinguish such sedimentary rock from ''metaquartzite'' produced by metamorphism. By extension, the term ''orthoquartzite'' has occasionally been more generally applied to any quartz-cemented [[quartz arenite]]. Orthoquartzite (in the narrow sense) is often 99% SiO<sub>2</sub> with only very minor amounts of iron oxide and trace resistant minerals such as [[zircon]], [[rutile]] and [[magnetite]]. Although few [[fossil]]s are normally present, the original texture and [[sedimentary]] structures are preserved.<ref name="Ireland-1974">{{cite journal|doi=10.1306/74D729F0-2B21-11D7-8648000102C1865D|author=Ireland, H. A.|year= 1974|title= Query: Orthoquartzite????|journal= Journal of Sedimentary Petrology|volume= 44|issue=1|pages=264–265}}</ref><ref name=oxford2013/>

The typical distinction between a true orthoquartzite and an ordinary quartz sandstone is that an orthoquartzite is so highly cemented that it will fracture across grains, not around them.<ref name=jackson1997/> This is a distinction that can be recognized in the [[Field work|field]]. In turn, the distinction between an orthoquartzite and a metaquartzite is the onset of recrystallization of existing grains. The dividing line may be placed at the point where strained quartz grains begin to be replaced by new, unstrained, small quartz grains, producing a ''mortar texture'' that can be identified in thin sections under a polarizing microscope. With increasing grade of metamorphism, further recrystallization produces ''foam texture'', characterized by polygonal grains meeting at triple junctions, and then ''porphyroblastic texture'', characterized by coarse, irregular grains, including some larger grains ([[porphyroblasts]]).<ref name=Howard2005/>

==Occurrence==
[[Image:Quartzite Mine in Kakwa Park.JPG|thumb|Abandoned quartzite mine in [[Kakwa Provincial Park]], British Columbia, Canada]]
In the United States, formations of quartzite can be found in some parts of Pennsylvania, the Washington DC area, eastern [[South Dakota]], Central Texas,<ref>{{cite web |last=Holm |first=E. H. |last2=Cline Jr. |first2=T. |last3=Nelson |first3=M.R. |title=SOUTH DAKOTA – 2002 Mineral Summary: Production, Exploration and Environmental Issues |url=http://www.state.sd.us/DENR/DES/Mining/2002stat.pdf |url-status=dead |archive-url=https://web.archive.org/web/20070512124912/http://www.state.sd.us/DENR/DES/Mining/2002stat.pdf |archive-date=May 12, 2007 |website=www.state.sd.us}}</ref> southwest [[Minnesota]],<ref>[http://www.dnr.state.mn.us/snas/naturalhistory.html Natural history – Minnesota's geology – SNAs: Minnesota DNR] {{webarchive |url=https://web.archive.org/web/20100309140357/http://www.dnr.state.mn.us/snas/naturalhistory.html |date=March 9, 2010 }}. Dnr.state.mn.us (2000-02-17). Retrieved on 2011-06-05.</ref> [[Devil's Lake State Park (Wisconsin)|Devil's Lake State Park]] in the [[Baraboo Range]] in [[Wisconsin]],<ref>[http://www.geology.wisc.edu/~maher/air/air14.htm Geology by Lightplane]. Geology.wisc.edu (1923-07-13). Retrieved on 2011-06-05.</ref> the [[Wasatch Range]] in [[Utah]],<ref>John W Gottman, ''Wasatch quartzite: A guide to climbing in the Wasatch Mountains,'' Wasatch Mountain Club (1979) {{ISBN|0-915272-23-7}}</ref> near Salt Lake City, Utah and as resistant ridges in the [[Appalachian Mountains|Appalachians]]<ref>{{cite journal |last1=Mitra |first1=Shankar |title=Regional variations in deformation mechanisms and structural styles in the central Appalachian orogenic belt |journal=GSA Bulletin |date=1 May 1987 |volume=98 |issue=5 |pages=569–590 |doi=10.1130/0016-7606(1987)98<569:RVIDMA>2.0.CO;2|bibcode=1987GSAB...98..569M }}</ref> and other mountain regions. Quartzite is also found in the Morenci Copper Mine in [[Arizona]].<ref>Kennedy, B. A. (ed.). [http://books.smenet.org/Surf_Min_2ndEd/sm-ch09-sc04-ss00-bod.cfm ''Surface Mining'', Chapter 9.4: Case Studies: Morenci/Metcalf] {{webarchive|url=https://web.archive.org/web/20070625010020/http://books.smenet.org/Surf_Min_2ndEd/sm-ch09-sc04-ss00-bod.cfm |date=2007-06-25 }} Society for Mining, Metallurgy, and Exploration, Undated Accessed May 28, 2007</ref> The town of [[Quartzsite, Arizona|Quartzsite]] in western Arizona derives its name from the quartzites in the [[Maria fold and thrust belt|nearby mountains]] in both Arizona and Southeastern California. A glassy ''vitreous quartzite'' has been described from the [[Belt Supergroup]] in the [[Coeur d'Alene, Idaho|Coeur d’Alene district]] of northern [[Idaho]].<ref>White, B.G. and Winston, D., 1982, The Revett/St Regis "transition zone" near the Bunker Hill mine, Coeur d’Alene district, Idaho: Idaho Bureau of Mines and Geology Bulletin 24</ref>

In Canada, the [[La Cloche Mountains]] in [[Ontario]] are composed primarily of white quartzite. Vast areas of [[Nova Scotia]] are underlain by quartzite.

[[Paleoproterozoic]] quartzite-[[rhyolite]] successions are common in the [[Precambrian]] [[basement (geology)|basement]] rock of western North America. The quartzites in these successions are interpreted as sedimentary beds deposited atop older [[greenstone belt]]s. The quartzite-rhyolite successions may record the formation of [[back-arc basins]] along the margin of [[Laurentia]], the ancient core of North America, between episodes of mountain building during the assembly of the continent. The quartzites are often nearly pure quartz, which is puzzling for sediments which must have eroded from igneous rock. Their purity may reflect unusual conditions of chemical weathering, at a time when the Earth's atmosphere was beginning to be oxygenated.<ref>{{cite journal |last1=Whitmeyer |first1=Steven |last2=Karlstrom |first2=Karl E. |title=Tectonic model for the Proterozoic growth of North America |journal=Geosphere |date=2007 |volume=3 |issue=4 |pages=220 |doi=10.1130/GES00055.1|doi-access=free }}</ref>

In [[Ireland]] areas of quartzite are found across the west and northwest, with [[Errigal]] in [[County Donegal]] as the most prominent outcrop. A good example of a quartzite area is on the [[Corraun Peninsula]] in [[County Mayo]], which has a very thin layer of Irish Atlantic Bog covering it.

In the United Kingdom, a craggy ridge of quartzite called the [[Stiperstones]] (early [[Ordovician]] – [[Arenig|Arenig Epoch]], 500 Ma) runs parallel with the [[Pontesford-Linley fault]], 6&nbsp;km north-west of the [[Long Mynd]] in south [[Shropshire]]. Also to be found in [[England]] are the [[Cambrian]] "[[The Wrekin|Wrekin]] quartzite" (in Shropshire), and the Cambrian "[[Hartshill]] quartzite" ([[Nuneaton]] area).<ref>{{cite book|author=Veena|title=Understanding Geology|year=2009|url=https://books.google.com/books?id=9dYw6kHptcQC&pg=PA145|access-date=5 June 2011|publisher=Discovery Publishing House|isbn=978-81-8356-461-8|pages=145–}}</ref> In [[Wales]], [[Holyhead Mountain]] and most of [[Holy Island, Anglesey|Holy island]] off [[Anglesey]] sport excellent [[Precambrian]] quartzite crags and cliffs. In the [[Scottish Highlands]], several mountains (e.g. [[Foinaven]], [[Arkle (Sutherland)|Arkle]]) composed of Cambrian quartzite can be found in the far north-west [[Moine Thrust Belt]] running in a narrow band from [[Loch Eriboll]] in a south-westerly direction to [[Skye]].<ref>John Blunden, (1975), ''The mineral resources of Britain: a study in exploitation and planning'', p. 281.</ref>

In [[continental Europe]], various regionally isolated quartzite deposits exist at surface level in a belt from the [[Rhenish Massif]] and the German Central Highlands into the Western [[Czech Republic]], for example in the [[Taunus]] and [[Harz]] mountains. In Poland, quartzite deposits at surface level exists in [[Świętokrzyskie Mountains]]. In Norway, deposits are quarried near [[Austertana]],<ref>{{cite web|url=https://www.aggbusiness.com/feature/lns-use-caterpillar-775g-trucks-austertana-quarry-norway|title=LNS use Caterpillar 775G trucks at Austertana quarry, Norway|access-date=2021-08-01|date=2013-06-11|publisher=Aggregates Business Europe}}</ref> which is one of the largest quarries in the world at {{convert|850000|t}} annually, and Mårnes near [[Sandhornøya]] with an output of {{convert|150000|t}} annually.<ref>{{cite web|url=https://www.miningnordics.com/companies/elkem-asa|title=Elkem ASA|access-date=2021-08-01|publisher=Mining in the Nordics}}</ref> Deposits are also quarried in [[Kragerø Municipality]], and several other deposits are known but not actively quarried.<ref>{{cite magazine|url=https://www.ngu.no/sites/default/files/Focus_11_2019_final_QUARTZ_RESOURCES_IN_NORWAY_Crop.pdf|title=Quartz Resources in Norway - A Varied Spectrum|access-date=2021-08-01|date=2019-02-26|magazine=NGU Focus|issue=11|publisher=The Geological Survey of Norway|first=Jan|last=Egil Wanvik|archive-date=2022-05-19|archive-url=https://web.archive.org/web/20220519154810/https://www.ngu.no/sites/default/files/Focus_11_2019_final_QUARTZ_RESOURCES_IN_NORWAY_Crop.pdf|url-status=dead}}</ref>

The highest mountain in [[Mozambique]], [[Monte Binga]] (2436 m), as well as the rest of the surrounding Chimanimani Plateau are composed of very hard, pale grey, Precambrian quartzite. Quartzite is also mined in Brazil for use in kitchen countertops.

==Uses==
[[File:Tutankhamun oriental institute Chicago.jpg|thumb|left|upright=0.6|Quartzite statue of an Egyptian Pharaoh, 14th century BCE<ref name="TutStatue">{{cite web | url=https://www.lib.uchicago.edu/collex/exhibits/discovery-collection-memory-oriental-institute-100/colossal-statue-tutankhamun/ | title=The Colossal Statue of Tutankhamun | publisher=[[University of Chicago]] Library | work=Discovery, Collection, Memory: The Oriental Institute at 100 | date=2019 | accessdate=12 September 2023}}</ref>]]
[[File:Biface Stellenbosch MHNT PRE 2009.0.195.1 Global fond.jpg|thumb|Quartzite biface [[hand axe]] from [[Stellenbosch]], South Africa]]
Quartzite is a decorative stone and may be used to cover walls, as roofing tiles, as flooring, and stairsteps. Its use for countertops in kitchens is expanding rapidly. It is harder and more resistant to stains than granite. Crushed quartzite is sometimes used in road construction.<ref name=MII /> High purity quartzite is used to produce [[ferrosilicon]], industrial [[silica]] sand, [[silicon]] and [[silicon carbide]].<ref>{{cite book|last=Krukowski|first=Stanley T.|title=Industrial minerals & rocks: commodities, markets, and uses|editor=Jessica Elzea Kogel |editor2=Nikhil C. Trivedi |editor3=James M. Barker |editor4=Stanley T. Krukowski|publisher=Society for Mining, Metallurgy, and Exploration (U.S.)|year=2006|edition=7|page=842|chapter=Specialty Silica Materials|isbn=0-87335-233-5|chapter-url=https://books.google.com/books?id=zNicdkuulE4C&pg=PA842}}</ref>
During the [[Paleolithic]], quartzite was used, along with [[flint]], [[quartz]], and other lithic raw materials, for making [[stone tools]].<ref>{{cite journal |last1=Seong |first1=Chuntaek |title=Quartzite and Vein Quartz as Lithic Raw Materials Reconsidered: A View from the Korean Paleolithic |journal=Asian Perspectives |date=2004 |volume=43 |issue=1 |pages=73–91 |doi=10.1353/asi.2004.0016 |url=http://scholarspace.manoa.hawaii.edu/bitstream/handle/10125/17202/AP-v43n1-73-91.pdf;sequence=1 |access-date=27 March 2022 |jstor=42928601|hdl=10125/17202 |s2cid=161224840 |hdl-access=free }}</ref> Prehistoric humans in the southeastern United States often made mortars out of quartzite stones.<ref>{{cite journal |last1=Reeves |first1=Bob |title=Mortars and Pestles of the Southeastern States |journal=Central States Archaeological Journal |date=April 2018 |volume=65 |issue=2 |pages=66–69 |jstor=44715697
}}</ref>

==Safety==
As quartzite is a form of silica, it is a possible cause for concern in various workplaces. Cutting, grinding, chipping, sanding, drilling, and polishing natural and manufactured stone products can release hazardous levels of very small, crystalline silica dust particles into the air that workers breathe.<ref>{{cite book |title=Hazard Alert - Worker Exposure to Silica during Countertop Manufacturing, Finishing and Installation |publisher=DHHS (NIOSH) |page=2 |url=https://www.osha.gov/Publications/OSHA3768.pdf |access-date=27 November 2019}}</ref> Crystalline silica of respirable size is a recognized human [[carcinogen]] and may lead to other diseases of the lungs such as [[silicosis]] and [[pulmonary fibrosis]].<ref>{{cite web |title=Silica (crystalline, respirable) |url=https://oehha.ca.gov/chemicals/silica-crystalline-respirable |website=OEHHA |publisher=California Office of Environmental Health Hazard Assessment |access-date=27 November 2019}}</ref><ref>{{cite book |title=Arsenic, Metals, Fibres and Dusts. A Review of Human Carcinogens |date=2012 |publisher=International Agency for Research on Cancer |isbn=978-92-832-1320-8 |pages=355–397 |edition=100C |url=https://www.ncbi.nlm.nih.gov/books/NBK304375/pdf/Bookshelf_NBK304375.pdf |access-date=27 November 2019}}</ref>

==Etymology==
The term ''quartzite'' is derived from {{langx|de|Quarzit}}.<ref>{{cite web | url=http://german.about.com/library/blvoc_gerloan.htm | title=German Loan Words in English | publisher=German.about.com | date=2010-06-22 | access-date=2011-06-05 | archive-url=https://web.archive.org/web/20110607060111/http://german.about.com/library/blvoc_gerloan2.htm |archive-date=2011-06-07 | url-status=dead}}</ref>

==Gallery==
<gallery widths="200px" heights="150px">
File:SwanPeakQuartziteOutcrop.jpg|Swan Peak Quartzite ([[Ordovician]]) exposed just north of [[Tony Grove Lake]], [[Cache County, Utah]]
File:View_of_Doso_Doyabi_from_Wheeler_Peak.jpg|The quartzite of the [[Prospect Mountain Formation]] at the top of [[Doso Doyabi]] in [[White Pine County, Nevada]]
Image:Normal view of Bo Quartzite.JPG|Quartzite from [[Salangen Municipality]], Troms county, Norway, showing elongate crystals associated with high [[Deformation (mechanics)|strain]] regimes
Image:Thin section image of quartzie.jpg|[[Thin section]] of quartzite from Salangen, Troms county, Norway, showing elongate crystals associated with high strain regimes
</gallery>
[[File:Metaquartzite.jpg|thumb|Quartzite pebble from Ontario, Canada ]]

==See also==
*[[Neomorphism]]

== References ==
{{reflist}}

== External links ==
{{Commons category}}
{{EB1911 poster|Quartzite}}
* [https://web.archive.org/web/20110725104655/http://www.cst.cmich.edu/users/dietr1rv/quartzite.htm R. V. Dietrich's GemRocks: Quartzite]
* [https://web.archive.org/web/20090521091447/http://geology.csupomona.edu/alert/metamorphic/quartzite.htm CSU Pomona Geology: Quartzite]
* [http://www.geology.ucdavis.edu/~cowen/~GEL115/115CH1.html Cowen's "The First Geologists" (chapter on Stone Age/''Homo habilis'' use of quartzite)] {{Webarchive|url=https://web.archive.org/web/20081013003720/http://www.geology.ucdavis.edu/~cowen/~GEL115/115CH1.html |date=2008-10-13 }}
* [https://web.archive.org/web/20100309140357/http://www.dnr.state.mn.us/snas/naturalhistory.html Minnesota Department of Natural Resources : Natural History: Minnesota's geology]
* [http://www.geology.wisc.edu/~maher/air/air14.htm Wisconsin's Baraboo Syncline (map and aerial photos of Baraboo quartzite quarries)]
* [https://web.archive.org/web/20070512124912/http://www.state.sd.us/DENR/DES/Mining/2002stat.pdf South Dakota 2002 Mineral Summary: Production, Exploration and Environmental Issues (including 2002 quartzite production)]
* [https://web.archive.org/web/20061128185851/http://sdww2heroes.tripod.com/zerrphotos/id1.html Big Sioux River: History of Sioux Falls and Quartzite Photos]

{{Silica minerals}}
{{Rock type}}
{{Authority control}}

[[Category:Quartzite formations| ]]
[[Category:Quartz varieties]]
[[Category:Metasedimentary rocks]]