View source for Chemistry:Beryl

{{short description|Gemstone: beryllium aluminium silicate}}
 <!--Except for access and archive dates-->
{{Infobox mineral
| boxbgcolor  = #91d1d1
| name        = Beryl
| category    = [[Chemistry:Cyclosilicate|Cyclosilicate]]
| image       = Beryl09.jpg
| imagesize   = 260px
| alt         = 
| caption     = Three varieties of beryl (left to right): [[Chemistry:Morganite|morganite]], [[Chemistry:Aquamarine (gem)|aquamarine]] and emerald
| formula     = {{chem2|Be3Al2Si6O18}}
| IMAsymbol=Brl<ref>{{Cite journal|last=Warr|first=L.N.|date=2021|title=IMA–CNMNC approved mineral symbols|journal=Mineralogical Magazine|volume=85|issue=3|pages=291–320|doi=10.1180/mgm.2021.43|bibcode=2021MinM...85..291W|s2cid=235729616|doi-access=free}}</ref>
| molweight   = 537.50&nbsp;g/mol
| strunz      = 9.CJ.05
| system      = [[Physics:Hexagonal crystal system|Hexagonal]]
| class       = Dihexagonal dipyramidal (6/mmm) <br/>[[Chemistry:H-M symbol|H-M symbol]]: (6/m 2/m 2/m)
| symmetry    = ''P''6/mcc
| unit cell   = ''a'' = 9.21&nbsp;[[Ångström|Å]], ''c'' = 9.19&nbsp;Å; ''Z''&nbsp;=&nbsp;2
| color       = Green, blue, yellow, colorless, pink, and others
| habit       = Prismatic to tabular crystals; radial, columnar; granular to compact massive
| twinning    = Rare
| cleavage    = Imperfect on  {0001}
| fracture    = Conchoidal to irregular
| tenacity    = Brittle
| mohs        = 7.5–8.0
| luster      = Vitreous to resinous
| polish      = 
| opticalprop = Uniaxial (−)
| refractive  = ''n''<sub>ω</sub> = 1.564–1.595<br /> ''n''<sub>ε</sub> = 1.568–1.602
| birefringence = ''δ'' = 0.0040–0.0070
| dispersion  = 
| pleochroism = Weak to distinct
| fluorescence= None (some fracture filling materials used to improve emerald's clarity do fluoresce, but the stone itself does not). Morganite has weak violet fluorescence.
| absorption  = 
| streak      = White
| gravity     = 2.63–2.92
| density     = 
| melt        = 
| fusibility  = 
| diagnostic  = 
| solubility  = 
| diaphaneity = Transparent to translucent
| other       = 
| references  =<ref name=Mindat819>{{cite web |url=http://www.mindat.org/min-819.html |title=Beryl |url-status=live |archive-url=https://web.archive.org/web/20071026035730/http://www.mindat.org/min-819.html |archive-date=2007-10-26 |df=dmy-all |website=mindat.org}}</ref><ref name=Webmineral>{{cite web |url=http://www.webmineral.com/data/Beryl.shtml |title=Beryl Mineral Data |archive-url=https://web.archive.org/web/20080512070647/http://webmineral.com/data/Beryl.shtml  |archive-date=2008-05-12 |df=dmy-all |website=webmineral.org |url-status=live}}</ref><ref name=HBM>{{cite web |url=http://rruff.geo.arizona.edu/doclib/hom/beryl.pdf |title=Beryl |date=2001 |publisher=Mineral Data Publishing |url-status=live |archive-url=https://web.archive.org/web/20111128222019/http://rruff.geo.arizona.edu/doclib/hom/beryl.pdf |archive-date=2011-11-28 |df=dmy-all}}</ref><ref name=Schumann2009>{{cite book |last=Schumann |first=Walter |title=Gemstones of the World |year=2009 |publisher=Sterling Publishing Co. |isbn=978-1-402-76829-3 |url=https://books.google.com/books?id=V9PqVxpxeiEC |access-date=2018-05-22 |url-status=live |archive-url=https://web.archive.org/web/20171120224035/https://books.google.com/books?id=V9PqVxpxeiEC |archive-date=2017-11-20 |df=dmy-all}}</ref>{{rp|page=[https://books.google.com/books?id=V9PqVxpxeiEC&pg=PA112 112]}}
  }}

'''Beryl''' ({{IPAc-en|ˈ|b|ɛr|əl}} {{respell|BERR|əl}}) is a [[Earth:Mineral|mineral]] composed of [[Chemistry:Beryllium|beryllium]] [[Chemistry:Aluminium|aluminium]] [[Chemistry:Silicate minerals#Cyclosilicates|silicate]] with the [[Chemistry:Chemical formula|chemical formula]] Be<sub>3</sub>Al<sub>2</sub>Si<sub>6</sub>O<sub>18</sub>.<ref>{{cite web |url=https://www.minerals.net/mineral/beryl.aspx |title=Beryl |website=www.minerals.net |access-date=2018-07-12 |df=dmy-all}}</ref> Well-known varieties of beryl include [[Chemistry:Emerald|emerald]] and [[Chemistry:Aquamarine (gem)|aquamarine]]. Naturally occurring,  [[Physics:Hexagonal crystal system|hexagonal]] [[Earth:Crystal|crystal]]s of beryl can be up to several meters in size, but [[Earth:Double terminated crystal|terminated crystals]] are relatively rare. Pure beryl is colorless, but it is frequently tinted by impurities; possible colors are green, blue, yellow, pink, and red (the rarest). It is an ore source of [[Chemistry:Beryllium|beryllium]].<ref name="Klein-2007">{{cite book|last1=Klein|first1=Cornelis|title=The Manual of Mineral Science (after James D. Dana)|last2=Dutrow|first2=Barbara|last3=Dana|first3=James Dwight|date=2007|publisher=J. Wiley|isbn=978-0-471-72157-4|edition=23rd|location=Hoboken, N.J.|oclc=76798190|}}</ref>
[[File:Béryl.jpg|thumb|upright=1.5|Main beryl producing countries]]

==Etymology==
The word ''beryl'' – {{lang-enm|beril}} – is borrowed, via {{lang-fro|beryl}} and {{lang-la|beryllus}}, from [[Social:Ancient Greek|Ancient Greek]] βήρυλλος ''bḗryllos'', which referred to a 'precious blue-green color-of-sea-water stone';<ref name=Mindat819/> from [[Social:Prakrit|Prakrit]] ''veruḷiya'', ''veḷuriya'' 'beryl'<ref name=Skeat-1993>{{cite book |first1=Walter W. |last1=Skeat |year=1993 |title=The Concise Dictionary of English Etymology |publisher=Wordsworth Editions |isbn=978-1-85326-311-8 |page=36 |url=https://books.google.com/books?id=aDhGlKL3h00C&pg=PA36}}</ref>{{efn|
Compare ''veruḷiya'' and ''veḷuriya'' to the pseudo-[[Social:Sanskrit|Sanskrit]]ization वैडूर्य ''vaiḍūrya'', meaning either "cat's eye" (gem), generic "[[Earth:Gemstone|jewel]]", or "[[Chemistry:Lapis lazuli|lapis lazuli]]" (gem). The [[Social:Folk etymology|folk etymology]] explains the gem name as meaning "[brought] from [the city of] Vidūra".<ref name=Skeat-1993/>
}}
which is ultimately of [[Social:Dravidian languages|Dravidian]] origin, maybe from the name of Belur or ''Velur'', a town in Karnataka, southern {{wipe|India}}.<ref>{{cite dictionary |title=beryl |dictionary=Merriam-Webster |url=http://www.merriam-webster.com/dictionary/beryl |access-date=January 27, 2014 |url-status=live |archive-url=https://web.archive.org/web/20131009130722/http://www.merriam-webster.com/dictionary/beryl |archive-date=October 9, 2013 |df=dmy-all}}</ref> The term was later adopted for the mineral beryl more exclusively.

When the first [[Engineering:Glasses|eyeglasses]] were constructed in 13th-century Italy, the lenses were made of beryl (or of [[Chemistry:Quartz|rock crystal]]) as glass could not be made clear enough. Consequently, glasses were named ''Brillen'' in German<ref>{{cite dictionary |editor-last=Kluge |editor-first=Alexander |dictionary=Etymologisches Wörterbuch der deutschen Sprache |edition=21 |year=1975 |title=Brillen}}</ref> (''bril'' in Dutch and ''briller'' in Danish).

==Deposits==
Beryl is a common mineral, and it is widely distributed in nature. It is found most commonly in [[Chemistry:Granite|granitic]] [[Earth:Pegmatite|pegmatite]]s, but also occurs in [[Chemistry:Mica|mica]] [[Chemistry:Schist|schist]]s, such as those of the Ural Mountains, and in [[Earth:Limestone|limestone]] in Colombia.<ref name=KleinHurlbut1993>{{cite book |last1=Klein |first1=Cornelis |last2=Hurlbut | first2=Cornelius S. Jr. |title=Manual of Mineralogy (after James D. Dana) |date=1993 |publisher=Wiley |location=New York |isbn=0-471-57452-X |edition=21st |page=472}}</ref> It is less common in ordinary granite and is only infrequently found in nepheline syenite. Beryl is often associated with [[Chemistry:Tin|tin]] and [[Chemistry:Tungsten|tungsten]] ore bodies formed as high-temperature hydrothermal veins. In granitic pegmatites, beryl is found in association with [[Chemistry:Quartz|quartz]], [[Chemistry:Potassium feldspar|potassium feldspar]], [[Chemistry:Albite|albite]], [[Chemistry:Muscovite|muscovite]], [[Chemistry:Biotite|biotite]], and [[Chemistry:Tourmaline|tourmaline]]. Beryl is sometimes found in metasomatic contacts of igneous intrusions with [[Earth:Gneiss|gneiss]], schist, or [[Earth:Carbonate rock|carbonate rock]]s.<ref name=Nesse2000>{{cite book |last1=Nesse |first1=William D. |title=Introduction to mineralogy |date=2000 |publisher=Oxford University Press |location=New York |isbn=978-0-19-510691-6 |page=301}}</ref> Common beryl, mined as beryllium ore, is found in small deposits in many countries, but the main producers are Russia, Brazil, and the United States.<ref name=KleinHurlbut1993/>

New England's pegmatites have produced some of the largest beryls found, including one massive crystal from the Bumpus Quarry in Albany, Maine with dimensions {{convert|5.5|by|1.2|m|ft|abbr=on}} with a mass of around {{convert|18|tonne|ST}}; it is New Hampshire's state mineral. {{As of|1999}}, the world's largest known naturally occurring crystal of any mineral is a crystal of beryl from Malakialina, Madagascar, {{convert|18|m|abbr=on}} long and {{convert|3.5|m|abbr=on}} in diameter, and weighing {{convert|380,000|kg|abbr=on}}.<ref>G. Cressey and I. F. Mercer, (1999) ''Crystals'', London, Natural History Museum, page 58</ref>

== Crystal habit and structure ==
[[File:Beryl Crystal Structure.png|alt=Beryl crystal structure with view down {{mvar|C}}&nbsp;axis|thumb|left|Beryl crystal structure with view down {{mvar|C}}&nbsp;axis]]
Beryl belongs to the [[Physics:Hexagonal crystal family|hexagonal crystal system]]. Normally beryl forms hexagonal columns but can also occur in massive [[Physics:Crystal habit|habits]]. As a [[Chemistry:Silicate minerals#Cyclosilicates|cyclosilicate]] beryl incorporates rings of silicate tetrahedra of {{chem2|Si6O18}} that are arranged in columns along the {{mvar|C}}&nbsp;axis and as parallel layers perpendicular to the {{mvar|C}}&nbsp;axis, forming channels along the {{mvar|C}}&nbsp;axis.<ref name="Klein-2007"/> These channels permit a variety of ions, neutral atoms, and molecules to be incorporated into the crystal thus disrupting the overall charge of the crystal permitting further substitutions in [[Chemistry:Aluminium|aluminium]], [[Chemistry:Silicon|silicon]], and [[Chemistry:Beryllium|beryllium]] sites in the crystal structure.<ref name="Klein-2007"/> These impurities give rise to the variety of colors of beryl that can be found. Increasing alkali content within the silicate ring channels causes increases to the [[Physics:Refractive index|refractive indices]] and [[Physics:Birefringence|birefringence]].<ref>{{cite book |title=An introduction to the rock-forming minerals |last1=Deer |first1=W.A. |last2=Howie |first2=R.A. |last3=Zussman |first3=J. |year=2013 |isbn=978-0-903-05627-4 |edition=Third |place=London, UK |oclc=858884283}}</ref>

== Human health impact ==
{{Main|Medicine:Acute beryllium poisoning|Medicine:Berylliosis}}
Beryl is a beryllium compound that is a known carcinogen with acute toxic effects leading to pneumonitis when inhaled.<ref>{{cite web |title=Concise International Chemical Assessment Document 32, Beryllium and Beryllium compounds |url=http://www.inchem.org/documents/cicads/cicads/cicad32.htm | access-date=2019-07-16 |df=dmy-all }}</ref> Care must thus be used when mining, handling, and refining these gems.<ref>{{cite web |url=https://nj.gov/health/eoh/rtkweb/documents/fs/3080.pdf |title=Hazardous Substance Fact Sheet: Beryl |date=April 2020 |publisher=New Jersey Department of Health and Human Services |access-date=2023-08-04}}</ref>

==Varieties==

===Aquamarine and maxixe===
{{Main|Chemistry:Aquamarine (gem)}}
[[File:Beryl-209736.jpg|thumb|left|Aquamarine]]

Aquamarine (from {{lang-la|aqua marina}}, "sea water"<ref>{{cite dictionary |title=aquamarine |url=https://www.merriam-webster.com/dictionary/aquamarine |dictionary=Merriam-Webster |access-date=2017-02-05 |url-status=live |archive-url=https://web.archive.org/web/20170206103438/https://www.merriam-webster.com/dictionary/aquamarine |archive-date=2017-02-06 |df=dmy-all}}</ref>) is a blue or [[Cyan|cyan]] variety of beryl. It occurs at most localities which yield ordinary beryl. The gem-gravel [[Earth:Placer mining|placer]] deposits of Sri Lanka contain aquamarine. Green-yellow beryl, such as that occurring in Brazil, is sometimes called ''chrysolite aquamarine''.<ref>{{cite journal |last=Owens |first=George |date=1957 |title=The Amateur Lapidary |journal=Rocks & Minerals |volume=32 |issue=9–10 |page=471 |doi=10.1080/00357529.1957.11766963}}</ref> The deep blue version of aquamarine is called ''maxixe''<ref>{{Cite book|last1=Grande|first1=Lance|url=https://books.google.com/books?id=RnE9Fa4pbn0C&q=aquamarine|title=Gems and Gemstones: Timeless Natural Beauty of the Mineral World|last2=Augustyn|first2=Allison|date=2009-11-15|publisher=University of Chicago Press|isbn=978-0-226-30511-0|page=125|language=en}}</ref> (pronounced mah-she-she).<ref>{{cite web |first=John J. |last=Bradshaw |url=https://www.gemguide.com/maxixe-beryl/ |title= Maxixe Beryl |date=September 1, 2018 |website=Gemworld |access-date=2023-08-04}}</ref> Its color results from a radiation-induced color center.<ref>{{cite book |last=Watkins |first=M. |year=2002 |title=Rediscovering Colors: A Study in Pollyanna Realism |place=Netherlands |publisher=Springer |page=21 |isbn=978-1-4020-0737-8}}</ref>

[[File:Aquamarin cut.jpg|thumb|Faceted aquamarine]]
The pale blue color of aquamarine is attributed to Fe<sup>2+</sup>. Fe<sup>3+</sup> ions produce golden-yellow color, and when both Fe<sup>2+</sup> and Fe<sup>3+</sup> are present, the color is a darker blue as in maxixe.<ref name=viana1>{{cite journal |last1=Viana |first1=R.R. |last2=da Costa |first2=G.M. |last3=de Grave |first3=E. |last4=Stern |first4=W.B. |last5=Jordt-Evangelista |first5=H. |year=2002 |title=Characterization of beryl (aquamarine variety) by Mössbauer spectroscopy |journal=Physics and Chemistry of Minerals |volume=29 |issue=1 |page=78 |doi=10.1007/s002690100210 |bibcode=2002PCM....29...78V|s2cid=96286267 }}</ref><ref name=blak>{{cite journal |last1=Blak |first1=Ana Regina |last2=Isotani |first2=Sadao |last3=Watanabe |first3=Shigueo |year=1983 |title=Optical absorption and electron spin resonance in blue and green natural beryl: A reply |journal=Physics and Chemistry of Minerals |volume=9 |issue=6 |page=279 |doi=10.1007/BF00309581 |bibcode=1983PCM.....9..279B|s2cid=97353580 }}</ref> Decoloration of maxixe by light or heat thus may be due to the charge transfer between Fe<sup>3+</sup> and Fe<sup>2+</sup>.<ref>{{cite journal |last1=Andersson |first1=Lars Olov |title=Comments on Beryl Colors and on Other Observations Regarding Iron-containing Beryls |journal=The Canadian Mineralogist |date=15 July 2019 |volume=57 |issue=4 |pages=551–566 |doi=10.3749/canmin.1900021|s2cid=200066862 }}</ref>
 
In the United States, aquamarines can be found at the summit of Mount Antero in the Sawatch Range in central Colorado, and in the New England and North Carolina pegmatites.<ref name=Sinkankas1964>{{cite book |last1=Sinkankas |first1=John |title=Mineralogy for amateurs. |date=1964 |publisher=Van Nostrand |location=Princeton, N.J. |isbn=0-442-27624-9 |pages=507–509}}</ref> Aquamarines are also present in the state of Wyoming, aquamarine has been discovered in the Big Horn Mountains, near Powder River Pass.<ref>{{cite journal |last1=Fritsch |first1=E. |last2=Shigley |first2=J.E. |year=1989 |title=Contribution to the identification of treated colored diamonds: diamonds with peculiar color-zoned pavilions |journal=The Quarterly Journal of the Gemological Institute of America |volume=25 |number=2 |pages=95–101}}</ref> Another location within the United States is the Sawtooth Range near Stanley, Idaho, although the minerals are within a wilderness area which prevents collecting.<ref>{{cite journal |last1=Kiilsgaard |first1=T.H. |last2=Freeman |first2=V.L. |last3=Coffman |first3=J.S. |title=Mineral resources of the Sawtooth Primitive Area, Idaho |journal=U.S. Geological Survey Bulletin |date=1970 |volume=1319-D |pages=D-108 |doi=10.3133/b1319D|doi-access=free }}</ref> In Brazil, there are mines in the states of Minas Gerais,<ref name=Sinkankas1964/> Espírito Santo, and [[Place:Bahia|Bahia]], and minorly in Rio Grande do Norte.<ref>{{cite book |last1=Cassedanne |first1=J. |last2=Philippo |first2=Simon |title=Minerals and Gem deposits of the eastern Brazilian pegmatites |date=2015 |publisher=Musée national d'histoire naturelle Luxembourg |pages=139–206 |url=https://www.researchgate.net/publication/313250718 |access-date=15 April 2022}}</ref> The mines of Colombia, Madagascar, Russia,<ref name=Sinkankas1964/> Namibia,{{sfn|Klein|Hurlbut|1993|p=472}} Zambia,<ref>{{cite journal |last1=Carranza |first1=E. J. M. |last2=Woldai |first2=T. |last3=Chikambwe |first3=E. M. |title=Application of Data-Driven Evidential Belief Functions to Prospectivity Mapping for Aquamarine-Bearing Pegmatites, Lundazi District, Zambia |journal=Natural Resources Research |date=March 2005 |volume=14 |issue=1 |pages=47–63 |doi=10.1007/s11053-005-4678-9|s2cid=129933245 }}</ref> Malawi, Tanzania, and Kenya<ref>{{cite book |last1=Yager |first1=T.R. |title=Minerals Yearbook |date=2007 |publisher=U.S. Geological Survey |pages=22.1, 27.1, 39.3 |url=https://books.google.com/books?id=IiMtBJI6sG0C |access-date=15 April 2022 }}</ref> also produce aquamarine.

=== Emerald ===
{{Main|Chemistry:Emerald}}
[[File:Béryl var. émeraude sur gangue (Muzo Mine Boyaca - Colombie) 15.jpg|thumb|left|Rough emerald on matrix]]
Emerald is green beryl, colored by around 2% [[Chemistry:Chromium|chromium]] and sometimes [[Chemistry:Vanadium|vanadium]].<ref name=color>{{cite web |url=http://minerals.caltech.edu/FILES/Visible/BERYL/Index.htm |title=Color in the beryl group |website=minerals.caltech.edu |access-date=2009-06-06 |department=Mineral Spectroscopy Server |publisher=California Institute of Technology |url-status=live |archive-url=https://web.archive.org/web/20110822012424/http://minerals.caltech.edu/FILES/Visible/BERYL/Index.htm |archive-date=2011-08-22 |df=dmy-all}}</ref><ref name=Hurlbut>{{cite book |last1=Hurlbut |first1=Cornelius S. Jr. |last2=Kammerling |first2=Robert C. |name-list-style=amp |year=1991 |title=Gemology |page=203 |publisher=John Wiley & Sons |place=New York |isbn=978-0-471-42224-2}}</ref> Most emeralds are highly [[Earth:Inclusion (mineral)|included]], so their brittleness (resistance to breakage) is classified as generally poor.<ref>{{cite web|title=Emerald Quality Factors|url=https://www.gia.edu/emerald-quality-factor|website=GIA.edu|publisher=Gemological Institute of America|access-date=1 November 2016|url-status=live|archive-url=https://web.archive.org/web/20161102090527/http://www.gia.edu/emerald-quality-factor|archive-date=November 2, 2016}}</ref>

The modern English word "emerald" comes via [[Social:Middle English|Middle English]] ''emeraude'', imported from modern French via [[Social:Old French|Old French]] ''ésmeraude'' and [[Social:Medieval Latin|Medieval Latin]] {{Lang|la-x-medieval|esmaraldus}}, from [[Social:Latin|Latin]] {{Lang|la|smaragdus}}, from [[Social:Ancient Greek|Greek]] {{lang|grc|{{math|σμάραγδος}}}} ''smaragdos'' meaning 'green gem'.{{efn|
The [[Social:Ancient Greek|Greek]] {{lang|grc|{{math|σμάραγδος}}}} (''smaragdos'') is used in the Semitic languages as  אזמרגד , ''izmargad'', as a loan-word meaning a precious emerald-colored stone. Greek ''smaragdos'' was used to translate the native Hebrew word {{lang|he|ברקת}}, ''bareket'', for one of the twelve listed stones in the Hoshen pectoral pendant of the Kohen HaGadol. The word ''bareket'' is also used to mean "lightning flash". It may be related to Akkadian ''baraqtu'', which means "emerald". In turn the semetic language words are possibly related to the [[Social:Sanskrit|Sanskrit]] word {{lang|sa|मरकत}} ''marakata'', meaning "green".<ref name=Fernie>{{cite book | last = Fernie |first = W.T., M.D. |year = 1906 |title = Precious Stones for Curative Wear |publisher = John Wright. & Co. }}</ref>{{unreliable source|date=October 2023|reason=The book was a pseudo-medical book on "magic" stones. The cited philologies seem dubious, and are certainly very dated. Considerably better editions of the Greek and Hebrew bible texts are now known, and in the past 120 years far many more ancient Semetic languages have been studied by competent linguists.}}
}}

[[File:Smaragd-G-EmpireTheWorldOfGems.jpg|thumb|right|Faceted emerald, {{cvt|1.07|carat}}, Colombia]]
Emeralds in antiquity were mined by the Egyptians and in what is now Austria, as well as Swat in contemporary {{wipe|Pakistan}}.<ref>{{cite journal |last1=Giuliani |first1=G. |last2=Chaussidon |first2=M. |last3=Schubnel |first3=H.J. |last4=Piat |first4=D.H. |last5=Rollion-Bard |first5=C. |last6=France-Lanord |first6=C. |last7=Giard |first7=D. |last8=de Narvaez |first8=D. |last9=Rondeau |first9=B. |year=2000 |title=Oxygen isotopes and emerald trade routes since antiquity |journal=Science |volume=287 |issue=5453 |pages=631–633 |pmid=10649992 |doi=10.1126/science.287.5453.631 |bibcode=2000Sci...287..631G}}</ref> A rare type of emerald known as a [[Chemistry:Trapiche emerald|trapiche emerald]] is occasionally found in the mines of Colombia. A trapiche emerald exhibits a "star" pattern; it has raylike spokes of dark carbon impurities that give the emerald a six-pointed radial pattern. It is named for the ''trapiche'', a grinding wheel used to process [[Biology:Sugarcane|sugarcane]] in the region. Colombian emeralds are generally the most prized due to their transparency and fire. Some of the rarest emeralds come from the two main emerald belts in the Eastern Ranges of the Colombian [[Place:Andes|Andes]]: Muzo and Coscuez west of the Altiplano Cundiboyacense, and Chivor and Somondoco to the east. Fine emeralds are also found in other countries, such as Zambia, {{wipe|Brazil}}, Zimbabwe, {{wipe|Madagascar}}, {{wipe|Pakistan}}, {{wipe|India}}, Afghanistan and {{wipe|Russia}}. In the US, emeralds can be found in Hiddenite, North Carolina. In 1998, emeralds were discovered in [[Earth:Yukon|Yukon]].

Emerald is a rare and valuable gemstone and, as such, it has provided the [[Finance:Incentive|incentive]] for developing synthetic emeralds. Both hydrothermal<ref>{{cite journal |author=Hosaka, M. |year=1991 |title=Hydrothermal growth of gem stones and their characterization |journal=Progress in Crystal Growth and Characterization of Materials |volume=21 |issue=1–4 |page=71 |doi=10.1016/0960-8974(91)90008-Z}}</ref> and ''flux-growth'' synthetics have been produced. The first commercially successful emerald synthesis process was that of Carroll Chatham.<ref>{{cite web |url=http://gemologyproject.com/wiki/index.php?title=Carroll_Chatham |title=Carroll Chatham |publisher=The Gemology Project |url-status=live |archive-url=https://web.archive.org/web/20110910055802/http://gemologyproject.com/wiki/index.php?title=Carroll_Chatham |archive-date=2011-09-10 |df=dmy-all}}</ref> The other large producer of flux emeralds was Pierre Gilson Sr., which has been on the market since 1964. Gilson's emeralds are usually grown on natural colorless beryl seeds which become coated on both sides. Growth occurs at the rate of {{convert|1|mm|in}} per month, a typical seven-month growth run producing emerald crystals of 7&nbsp;mm of thickness.<ref>{{cite book |last=Nassau |first=K. |date=1980 |title=Gems Made by Man |publisher=Gemological Institute of America |isbn=978-0-873-11016-7}}</ref> The green color of emeralds is widely attributed to presence of Cr<sup>3+</sup> ions.<ref name=ibragim>{{cite journal |last1=Ibragimova |first1=E.M.|last2=Mukhamedshina |first2=N.M. |last3=Islamov |first3=A.Kh.|year=2009 |title=Correlations between admixtures and color centers created upon irradiation of natural beryl crystals  |journal=Inorganic Materials |volume=45 |issue=2 |page=162  |doi=10.1134/S0020168509020101|s2cid=96344887}}</ref><ref name=viana1/><ref name=blak/> Intensely green beryls from Brazil, Zimbabwe and elsewhere in which the color is attributed to [[Chemistry:Vanadium|vanadium]] have also been sold and certified as emeralds.<ref>{{cite book |last=Thomas |first=Arthur |year=2008 |title=Gemstones: Properties, Identification and Use |location=London |publisher=New Holland |pages=77–78 |isbn=978-1-845-37602-4}}</ref><ref>{{cite book |last1=Behmenburg |first1=Christa |last2=Conklin |first2=Lawrence |last3=Giuliani |first3=Gaston |last4=Glas |first4=Maximilian |last5=Gray |first5=Patricia |last6=Gray |first6=Michael |editor1-last=Giuliani |editor1-first=Gaston |editor2-last=Jarnot |editor2-first=Miranda |editor3-last=Neumeier |editor3-first=Gunther |editor4-last=Ottaway |editor4-first=Terri |editor5-last=Sinkankas |editor5-first=John |date=January 2002 |title=Emeralds of the World |series=ExtraLapis |volume=2 |place=East Hampton, CT |publisher=Lapis International |pages=75–77 |isbn=978-0-971-53711-8}}</ref><ref>{{cite book |last1=Deer |first1=W.A. |last2=Zussman |first2=J. |last3=Howie |first3=R.A. |year=1997 |title=Disilicates and Ring Silicates |series=Rock-forming Minerals |volume=1B | edition=2 |location=Bath |publisher=Geological Society of London |pages=393–394 |isbn=978-1-897-79989-5}}</ref>

===Golden beryl and heliodor===
[[File:Heliodor-G-EmpireTheWorldOfGems.jpg|thumb|right|Faceted golden beryl, {{cvt|48.75|carat}}, Brazil]]
''Golden beryl'' can range in colors from pale yellow to a brilliant gold. Unlike [[Chemistry:Emerald|emerald]], golden beryl generally has very few flaws. The term "golden beryl" is sometimes synonymous with ''heliodor'' (from Greek ''hēlios – ἥλιος'' "sun" + ''dōron – δῶρον'' "gift") but golden beryl refers to pure yellow or golden yellow shades, while heliodor refers to the greenish-yellow shades. The golden yellow color is attributed to Fe<sup>3+</sup> ions.<ref name=color/><ref name=ibragim/> Both golden beryl and heliodor are used as gems. Probably the largest cut golden beryl is the flawless {{convert|2054|carat|adj=on|lk=in}} stone on display in the Hall of Gems, [[Place:Washington, D.C.|Washington, D.C.]], United States.<ref>{{cite book |last=Thomas |first=Arthur |year=2007 |title=Gemstones |page=77 |url=https://books.google.com/books?id=MPZK8ILOSR0C&pg=PA77 |via=Google Books |publisher=New Holland Publishers |isbn=978-1-845-37602-4 }}{{Dead link|date=October 2023 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>
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===Goshenite===
{{Main|Chemistry:Goshenite (gem)}}
[[File:Goshénite.jpg|thumb|left|Goshenite]]
[[File:Goshenit-G-EmpireTheWorldOfGems.jpg|thumb|right|Faceted goshenite, {{cvt|1.88|carat}}, Brazil]]
Colorless beryl is called ''goshenite''. The name originates from Goshen, Massachusetts, where it was originally discovered. In the past, goshenite was used for manufacturing eyeglasses and lenses owing to its transparency. Nowadays, it is most commonly used for gemstone purposes.<ref>{{cite web |url=http://www.galleries.com/minerals/gemstone/goshenit/goshenit.htm |title=Goshenite, the colorless variety of beryl |access-date=2009-06-06 |df=dmy-all |url-status=live |archive-url=https://web.archive.org/web/20090630132542/http://www.galleries.com/minerals/gemstone/goshenit/goshenit.htm |archive-date=2009-06-30 |publisher=Amethyst Galleries}}</ref><ref>{{cite web |url=http://opticalmineralogy.com/the-silicates-mineral-class/goshenite-gem/ |title=Goshenite Gem |date=March 2, 2009 |website=Optical Mineralogy.com |access-date=2009-06-06 |df=dmy-all |url-status=live |archive-url=https://web.archive.org/web/20090709230558/http://opticalmineralogy.com/the-silicates-mineral-class/goshenite-gem/ |archive-date=2009-07-09}}</ref>

The gem value of goshenite is relatively low. However, goshenite can be colored yellow, green, pink, blue and in intermediate colors by irradiating it with high-energy particles. The resulting color depends on the content of Ca, Sc, Ti, V, Fe, and Co impurities.<ref name=ibragim/>
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===Morganite===
{{Main|Chemistry:Morganite (gem)}}
[[File:Beryl-Quartz-morganite brazil1.jpg|thumb|left|Morganite]]
[[File:Morganit-G-EmpireTheWorldOfGems.jpg|thumb|right|Faceted morganite, {{cvt|2.01|carat}}, Brazil]]
Morganite, also known as "pink beryl", "rose beryl", "pink emerald" (which is not a legal term according to the new Federal Trade Commission Guidelines and Regulations), and "cesian (or ''caesian'') beryl", is a rare light pink to rose-colored [[Earth:Gemstone|gem]]-quality variety of beryl. Orange/yellow varieties of morganite can also be found, and color banding is common. It can be routinely heat treated to remove patches of yellow and is occasionally treated by irradiation to improve its color. The pink color of morganite is attributed to Mn<sup>2+</sup> ions.<ref name=color/> 

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===Red beryl===
{{Main|Chemistry:Red beryl}}
[[File:Beryl-235618.jpg|thumb|left|Red beryl]]
Red variety of beryl (the "bixbite") was first described in 1904 for an occurrence, its [[Earth:Type locality (geology)|type locality]], at Maynard's Claim (Pismire Knolls), Thomas Range, Juab County, Utah.<ref name=Mindat690>{{cite web |url=http://www.mindat.org/min-690.html |title=Red Beryl |website=www.mindat.org |url-status=live |archive-url=https://web.archive.org/web/20131203010036/http://www.mindat.org/min-690.html |archive-date=2013-12-03 |df=dmy-all}}</ref><ref name=Ege/> The dark red color is attributed to Mn<sup>3+</sup> ions.<ref name=color/> Old synonym "bixbite" is deprecated from the CIBJO because of the possibility of confusion with the mineral [[Chemistry:Bixbyite|bixbyite]] (both named after mineralogist Maynard Bixby).<ref>{{Cite web |url=http://www.minerals.net/mineral/beryl.aspx |title=The Mineral Beryl |website=Minerals.net |access-date=2017-08-28 |url-status=live |archive-url=https://web.archive.org/web/20170828185252/http://www.minerals.net/mineral/beryl.aspx |archive-date=2017-08-28 |df=dmy-all}}</ref> Red "bixbite" beryl formerly was marketed as "red" or "scarlet emerald", but these terms involving "Emerald" terminology are now prohibited in the US.<ref>{{CodeFedReg|16|23|26}}</ref>

[[File:RedBeryl-G-EmpireTheWorldOfGems.jpg|thumb|right|Faceted red beryl, {{cvt|0.56|carat}}, Utah, US]]
Red beryl is very rare and has only been reported from a handful of North American locations: Wah Wah Mountains, Beaver County, Utah; Paramount Canyon, Round Mountain, Juab County, Utah; and Sierra County, New Mexico, although this locality does not often produce gem-grade stones.<ref name=Mindat690/> The bulk of gem-grade red beryl comes from the Ruby-Violet Claim in the Wah Wah Mts. of midwestern Utah, discovered in 1958 by Lamar Hodges, of [[Place:Fillmore, Utah|Fillmore, Utah]], while he was prospecting for [[Chemistry:Uranium|uranium]].<ref>{{cite web |title=Red Emerald History |url=http://www.redemerald.com/history.html |website=RedEmerald.com  |access-date=2007-11-21 |df=dmy-all |url-status=live |archive-url=https://web.archive.org/web/20071203052138/http://www.redemerald.com/history.html |archive-date=2007-12-03}}</ref> Red beryl has been known to be confused with [[Chemistry:Pezzottaite|pezzottaite]], a [[Chemistry:Caesium|caesium]] analog of beryl, found in Madagascar and, more recently, Afghanistan; cut gems of the two varieties can be distinguished by their difference in [[Physics:Refractive index|refractive index]], and the rough crystals easily by their differing crystal systems (pezzottaite trigonal, red beryl hexagonal). Synthetic red beryl is also produced.<ref>{{cite web |url=http://www.gemstoneslist.com/bixbite.html |title=Bixbite |website=The Gemstone List |url-status=live |archive-url=https://web.archive.org/web/20160312090712/http://www.gemstoneslist.com/bixbite.html |archive-date=2016-03-12 |df=dmy-all}}</ref> Like emerald and unlike most other varieties of beryl, the red ones are usually highly included.

While gem beryls are ordinarily found in pegmatites and certain metamorphic stones, red beryl occurs in topaz-bearing [[Earth:Rhyolite|rhyolite]]s.<ref>{{Cite web |url=https://www.gemsociety.org/article/red-beryl-jewelry-and-gemstone-information/ |title=Red beryl value, price, and jewelry information |publisher=International Gem Society |access-date=2017-08-28 |url-status=live |archive-url=https://web.archive.org/web/20170828192834/https://www.gemsociety.org/article/red-beryl-jewelry-and-gemstone-information/ |archive-date=2017-08-28 |df=dmy-all}}</ref> It is formed by crystallizing under low pressure and high temperature from a pneumatolytic phase along fractures or within near-surface miarolitic cavities of the rhyolite. Associated minerals include bixbyite, [[Chemistry:Quartz|quartz]], [[Chemistry:Orthoclase|orthoclase]], [[Chemistry:Topaz|topaz]], [[Chemistry:Spessartine|spessartine]], [[Chemistry:Pseudobrookite|pseudobrookite]] and [[Chemistry:Hematite|hematite]].<ref name=Ege>{{cite magazine |first=Carl |last=Ege |title=What gemstone is found in Utah that is rarer than diamond and more valuable than gold? |date=September 2002 |magazine=Survey Notes |volume=34 |issue=3 |url=http://geology.utah.gov/surveynotes/gladasked/gladberyl.htm |access-date=2011-07-02 |url-status=live |archive-url=https://web.archive.org/web/20101108170752/http://www.geology.utah.gov/surveynotes/gladasked/gladberyl.htm |archive-date=2010-11-08 |df=dmy-all}}</ref>
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==Footnotes==
{{notelist}}

==See also==
* {{annotated link|Chemistry:Chrysoberyl}}
* {{annotated link|Earth:List of minerals}}
* List of emeralds by size

==References==
{{reflist|25em}}

==Further reading==
* {{cite book |last1=Sinkankas |first1=John |date=1994 |title=Emerald & Other Beryls |publisher=Geoscience Press |isbn=978-0-801-97114-3}}

==External links==
*{{Cite AmCyc|wstitle=Beryl |short=x}}

{{Gemstone}}
{{Jewellery}}
{{ores}}

[[Category:Beryl group|*]]
[[Category:Hexagonal minerals]]

{{Sourceattribution|Beryl}}