Editing Quartz (section)

== Uses ==

Quartz is the most common material identified as the mystical substance [[maban]] in [[Australian Aboriginal mythology]]. It is found regularly in passage tomb cemeteries in Europe in a burial context, such as [[Newgrange]] or [[Carrowmore]] in [[Republic of Ireland|Ireland]]. Quartz was also used in [[Prehistoric Ireland]], as well as many other countries, for [[stone tool]]s; both vein quartz and rock crystal were [[knapping|knapped]] as part of the [[lithic technology]] of the prehistoric peoples.<ref>{{Cite web |url=http://www.lithicsireland.ie/phd_quartz_lithic_technology_chap_3.html |title=Driscoll, Killian. 2010. Understanding quartz technology in early prehistoric Ireland |access-date=19 July 2017 |archive-url=https://web.archive.org/web/20170625005416/http://www.lithicsireland.ie/phd_quartz_lithic_technology_chap_3.html |archive-date=25 June 2017 |url-status=live  }}</ref>

While [[jade]] has been since earliest times the most prized semi-precious stone for carving in [[East Asia]] and [[Pre-Columbian era|Pre-Columbian]] America, in Europe and the Middle East the different varieties of quartz were the most commonly used for the various types of [[Jewellery|jewelry]] and [[hardstone carving]], including [[engraved gem]]s and [[cameo (carving)|cameo gems]], [[rock crystal vase]]s, and extravagant vessels. The tradition continued to produce objects that were very highly valued until the mid-19th century, when it largely fell from fashion except in jewelry. Cameo technique exploits the bands of color in onyx and other varieties.

Efforts to synthesize quartz began in the mid-nineteenth century as scientists attempted to create minerals under laboratory conditions that mimicked the conditions in which the minerals formed in nature: German geologist [[Karl Emil von Schafhäutl]] (1803–1890) was the first person to synthesize quartz when in 1845 he created microscopic quartz crystals in a [[Pressure cooking|pressure cooker]].<ref>{{cite journal |first=Karl Emil |last=von Schafhäutl |title=Die neuesten geologischen Hypothesen und ihr Verhältniß zur Naturwissenschaft überhaupt (Fortsetzung) |trans-title=The latest geological hypotheses and their relation to science in general (continuation) |journal=Gelehrte Anzeigen |volume=20 |issue=72 |date=10 April 1845 |pages=577–584 |location=[[Munich|München]] |publisher=im Verlage der königlichen Akademie der Wissenschaften, in Commission der Franz'schen Buchhandlung |url=https://archive.org/stream/gelehrteanzeige06wissgoog#page/n298/mode/1up |oclc=1478717}} From page 578:  5) ''Bildeten sich aus Wasser, in welchen ich im Papinianischen Topfe frisch gefällte Kieselsäure aufgelöst hatte, beym Verdampfen schon nach 8 Tagen Krystalle, die zwar mikroscopisch, aber sehr wohl erkenntlich aus sechseitigen Prismen mit derselben gewöhnlichen Pyramide bestanden.'' ( 5) There formed from water in which I had dissolved freshly precipitated silicic acid in a Papin pot [i.e., pressure cooker], after just 8&nbsp;days of evaporating, crystals, which albeit were microscopic but consisted of very easily recognizable six-sided prisms with their usual pyramids.)</ref> However, the quality and size of the crystals that were produced by these early efforts were poor.<ref>Byrappa, K. and Yoshimura, Masahiro (2001) ''Handbook of Hydrothermal Technology''. Norwich, New York: Noyes Publications. {{ISBN|008094681X}}. [https://books.google.com/books?id=-rYel1Q2HB8C&pg=PA53 Chapter 2:  History of Hydrothermal Technology].</ref>

Elemental impurity incorporation strongly influences the ability to process and utilize quartz. Naturally occurring quartz crystals of extremely high purity, necessary for the crucibles and other equipment used for growing [[Monocrystalline silicon|silicon]] [[Wafer (electronics)|wafers]] in the [[semiconductor]] industry, are expensive and rare. These high-purity quartz are defined as containing less than 50 ppm of impurity elements.<ref>{{Cite journal |last1=Götze |first1=Jens |last2=Pan |first2=Yuanming |last3=Müller |first3=Axel |date=October 2021 |title=Mineralogy and mineral chemistry of quartz: A review |journal=Mineralogical Magazine |language=en |volume=85 |issue=5 |pages=639–664 |doi=10.1180/mgm.2021.72 |bibcode=2021MinM...85..639G |s2cid=243849577 |issn=0026-461X|doi-access=free }}</ref> A major mining location for high purity quartz is the [[Spruce Pine Mining District]] in [[Spruce Pine, North Carolina]], United States.<ref>{{cite news|url=http://news.bbc.co.uk/2/hi/technology/8178580.stm|author=Nelson, Sue|title=Silicon Valley's secret recipe|work=BBC News|date=2009-08-02|access-date=16 September 2009|archive-url=https://web.archive.org/web/20090805092039/http://news.bbc.co.uk/2/hi/technology/8178580.stm|archive-date=5 August 2009|url-status=live}}</ref> Quartz may also be found in [[Caldoveiro Peak]], in [[Asturias]], Spain.<ref>{{cite web
 |title        = Caldoveiro Mine, Tameza, Asturias, Spain
 |publisher    = mindat.org
 |url          = https://www.mindat.org/loc-122679.html
 |access-date  = 15 February 2018
 |archive-url  = https://web.archive.org/web/20180212083356/https://www.mindat.org/loc-122679.html
 |archive-date = 12 February 2018
 |url-status     = live
 |df           = dmy-all
}}</ref>

By the 1930s, the electronics industry had become dependent on quartz crystals. The only source of suitable crystals was Brazil; however, [[World War II]] disrupted the supplies from Brazil, so nations attempted to synthesize quartz on a commercial scale. German mineralogist Richard Nacken (1884–1971) achieved some success during the 1930s and 1940s.<ref>Nacken, R. (1950) "Hydrothermal Synthese als Grundlage für Züchtung von Quarz-Kristallen" (Hydrothermal synthesis as a basis for the production of quartz crystals), ''Chemiker Zeitung'', '''74''' : 745–749.</ref> After the war, many laboratories attempted to grow large quartz crystals. In the United States, the U.S. Army Signal Corps contracted with [[Bell Labs|Bell Laboratories]] and with the [[Brush Development Company]] of Cleveland, Ohio to synthesize crystals following Nacken's lead.<ref>{{Cite journal | doi = 10.1126/science.107.2781.393| pmid = 17783928| title = The Laboratory Growing of Quartz| journal = Science| volume = 107| issue = 2781| pages = 393–394| year = 1948| last1 = Hale | first1 = D. R.| bibcode = 1948Sci...107..393H}}</ref><ref>{{Cite journal| doi = 10.1109/MIM.2011.6041381| url = http://tf.nist.gov/general/pdf/2534.pdf| title = The evolution of time measurement, Part 2: Quartz clocks [Recalibration]| journal = IEEE Instrumentation & Measurement Magazine| volume = 14| issue = 5| pages = 41–48| year = 2011| last1 = Lombardi| first1 = M.| s2cid = 32582517| access-date = 30 March 2013| archive-url = https://web.archive.org/web/20130527002612/http://tf.nist.gov/general/pdf/2534.pdf| archive-date = 27 May 2013| url-status = live| df = dmy-all}}</ref> (Prior to World War II, Brush Development produced piezoelectric crystals for record players.) By 1948, Brush Development had grown crystals that were 1.5 inches (3.8&nbsp;cm) in diameter, the largest at that time.<ref>[https://books.google.com/books?id=pCQDAAAAMBAJ&pg=PA148 "Record crystal"], ''Popular Science'', '''154''' (2) :  148 (February 1949).</ref><ref>Brush Development's team of scientists included:  Danforth R. Hale, Andrew R. Sobek, and Charles Baldwin Sawyer (1895–1964).  The company's U.S. patents included:
*  Sobek, Andrew R. "Apparatus for growing single crystals of quartz", {{US Patent|2674520}}; filed:  11 April 1950; issued: 6 April 1954.
*  Sobek, Andrew R. and Hale, Danforth R. "Method and apparatus for growing single crystals of quartz", {{US Patent|2675303}}; filed:  11 April 1950; issued:  13 April 1954.
*  Sawyer, Charles B. "Production of artificial crystals", {{US Patent|3013867}}; filed:  27 March 1959; issued:  19 December 1961.  (This patent was assigned to Sawyer Research Products of Eastlake, Ohio.)</ref> By the 1950s, [[hydrothermal synthesis]] techniques were producing synthetic quartz crystals on an industrial scale, and today virtually all the quartz crystal used in the modern electronics industry is synthetic.<ref name="buisson-arnaud-1994"/>

An early use of the piezoelectricity of quartz crystals was in [[phonograph]] pickups. One of the most common piezoelectric uses of quartz today is as a [[crystal oscillator]]. The [[Crystal oscillator|quartz oscillator]] or resonator was first developed by [[Walter Guyton Cady]] in 1921.<ref>{{cite journal|author=Cady, W. G. |year=1921|title=The piezoelectric resonator|journal=Physical Review |volume=17|pages=531–533|doi=10.1103/PhysRev.17.508|url=https://zenodo.org/record/2523161}}</ref><ref>{{cite web|url=http://invention.smithsonian.org/centerpieces/quartz/inventors/cady.html |title=The Quartz Watch&nbsp;– Walter Guyton Cady |publisher=The Lemelson Center, National Museum of American History, [[Smithsonian Institution]] |url-status=dead |archive-url=https://web.archive.org/web/20090104143758/http://invention.smithsonian.org/centerpieces/quartz/inventors/cady.html |archive-date=4 January 2009 }}</ref> [[G. W. Pierce|George Washington Pierce]] designed and patented [[Pierce oscillator|quartz crystal oscillators]] in 1923.<ref>{{cite journal|jstor=20026061|author=Pierce, G. W. |year=1923|title=Piezoelectric crystal resonators and crystal oscillators applied to the precision calibration of wavemeters|journal=Proceedings of the American Academy of Arts and Sciences|volume=59|issue=4|pages=81–106|doi=10.2307/20026061|hdl=2027/inu.30000089308260 |hdl-access=free}}</ref><ref>Pierce, George W. "Electrical system", {{US Patent|2133642}}, filed: 25 February 1924; issued:  18 October 1938.</ref><ref>{{cite web|url=http://invention.smithsonian.org/centerpieces/quartz/inventors/pierce.html |title=The Quartz Watch&nbsp;– George Washington Pierce |publisher=The Lemelson Center, National Museum of American History, [[Smithsonian Institution]] |url-status=dead |archive-url=https://web.archive.org/web/20090104145422/http://invention.smithsonian.org/centerpieces/quartz/inventors/pierce.html |archive-date=4 January 2009 }}</ref> The [[quartz clock]] is a familiar device using the mineral. Warren Marrison created the first quartz oscillator clock based on the work of Cady and Pierce in 1927.<ref>{{cite web|url=http://invention.smithsonian.org/centerpieces/quartz/inventors/clock.html |title=The Quartz Watch&nbsp;– Warren Marrison |publisher=The Lemelson Center, National Museum of American History, [[Smithsonian Institution]] |url-status=dead |archive-url=https://web.archive.org/web/20090125110103/http://invention.smithsonian.org/centerpieces/quartz/inventors/clock.html |archive-date=25 January 2009 }}</ref> The resonant frequency of a quartz crystal oscillator is changed by mechanically loading it, and this principle is used for very accurate measurements of very small mass changes in the [[quartz crystal microbalance]] and in [[thin-film thickness monitor]]s.<ref name="Sauerbrey_1959">{{Cite journal |author-last=Sauerbrey |author-first=Günter Hans |author-link=Günter Sauerbrey |title=Verwendung von Schwingquarzen zur Wägung dünner Schichten und zur Mikrowägung |language=de |doi=10.1007/BF01337937 |journal=[[Zeitschrift für Physik]] |publisher=[[Springer-Verlag]] |volume=155 |issue=2 |pages=206–222 |date=April 1959 |orig-year=1959-02-21 |issn=0044-3328 |bibcode=1959ZPhy..155..206S |s2cid=122855173 |url=http://jmfriedt.sequanux.org/t/sauerbrey.pdf |access-date=2019-02-26 |url-status=live |archive-url=https://web.archive.org/web/20190226103453/http://jmfriedt.sequanux.org/t/sauerbrey.pdf |archive-date=2019-02-26}} (NB. This was partially presented at Physikertagung in Heidelberg in October 1957.)</ref>

<gallery class="center" widths="170px" heights="200px">
File:Milan Jug with cut festoon decoration.jpg|Rock crystal jug with cut festoon decoration by [[Milan]] workshop from the second half of the 16th century, [[National Museum, Warsaw|National Museum]] in [[Warsaw]]. The city of Milan, apart from [[Prague]] and [[Florence]], was the main [[Renaissance]] centre for crystal cutting.<ref>{{cite book |title=The International Antiques Yearbook |year=1972 |page=78 |publisher=Studio Vista Limited |url=https://books.google.com/books?id=BVcvAQAAIAAJ|quote=Apart from Prague and Florence, the main Renaissance centre for crystal cutting was Milan.}}</ref>
File:Prototype synthetic quartz autoclave 1959.jpg|Synthetic quartz crystals produced in the autoclave shown in [[Western Electric]]'s pilot hydrothermal quartz plant in 1959
File:Ewer birds Louvre MR333.jpg|[[Fatimid Caliphate|Fatimid]] ewer in carved rock crystal (clear quartz) with gold lid, {{Circa|1000}}
</gallery>

Almost all the industrial demand for quartz crystal (used primarily in electronics) is met with synthetic quartz produced by the hydrothermal process. However, synthetic crystals are less prized for use as gemstones.<ref>{{cite web |title=Hydrothermal Quartz |url=https://www.gemselect.com/other-info/synthetic-quartz.php |website=Gem Select |publisher=GemSelect.com |access-date=28 November 2020}}</ref> The popularity of [[crystal healing]] has increased the demand for natural quartz crystals, which are now often mined in [[developing countries]] using primitive mining methods, sometimes involving [[child labor]].<ref>{{Cite news|url=https://www.theguardian.com/lifeandstyle/2019/sep/17/healing-crystals-wellness-mining-madagascar|title=Dark crystals: the brutal reality behind a booming wellness craze|last=McClure|first=Tess|date=2019-09-17|work=The Guardian|access-date=2019-09-25|language=en-GB|issn=0261-3077}}</ref>