{{Short description|Zeolite mineral}} {{Infobox mineral | name = Barrerite | category = Tectosilicate minerals | group = Zeolite group, stilbite subgroup | image = Barrerite-27538.jpg | imagesize = 260px | alt = | caption = Barrerite from Kuiu Island, Alaska, USA. | formula = {{chem2| Na2(Si7Al2)O18*6H2O}} |IMAsymbol=Bre<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> | strunz = 9.GE.15 | color = White, pink | system = Orthorhombic | class = Dipyramidal (mmm) <br/>H-M symbol: (2/m 2/m 2/m) | symmetry = ''Amma'' | cleavage = Perfect | mohs = 3 - 4 | luster = Vitreous-glassy | diaphaneity = Transparent to translucent | streak = White | refractive = n<sub>α</sub> = 1.479 n<sub>β</sub> = 1.485 n<sub>γ</sub> = 1.489 | opticalprop = Biaxial (-) | gravity = 2.13 | references = <ref>{{Cite web |title=Mineralienatlas - Fossilienatlas |url=https://www.mineralienatlas.de/lexikon/index.php/MineralData?lang=de&mineral=Barrerite |access-date=2023-06-29 |website=www.mineralienatlas.de |language=en}}</ref><ref>{{Cite web |title=Barrerite Mineral Data |url=http://webmineral.com/data/Barrerite.shtml |access-date=2023-06-29 |website=webmineral.com}}</ref><ref name="Mindat">{{Cite web |title=Barrerite |url=http://www.mindat.org/min-536.html}}</ref> }}
'''Barrerite''' is a tectosilicate mineral and a member of the zeolite family. It is one of the rarer zeolites. It was named for Richard Barrer, a New Zealand-born chemist.<ref name=Mindat/>
Barrerite crystal are white to pinkish, with a vitreous-glassy luster. The crystal system is orthorhombic and is flat and tabular in appearance. It has a Mohs hardness of 3 to 4 and its cleavage is perfect. Barrerite has a white streak and a density of 2.13.
It was first described in 1974 for an occurrence in Sardinia at Sant' Efisio Tower on Cape Pula in Cagliari Province.<ref name=Mindat/> It has also been reported from Rocky Pass, Kuiu Island, Alaska, and a few other localities.
==References== {{reflist}}
{{Commons category|Barrerite|position=left}}
Category:Stilbite subgroup Category:Orthorhombic minerals Category:Minerals in space group 63
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