{{Short description|Rare calcium iron arsenite mineral}} {{Infobox mineral | name = Cafarsite | category = Arsenites | image = Cafarsite-tmix07-154b.jpg | caption = Cafarsite on granite | formula = {{chem|Ca|8|(|Ti,Fe|2+|,Fe|3+|,Mn)|6–7|(AsO|3|)|12}}·{{chem|4H|2|O}} | IMAsymbol=Caf<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 = 2,230.31 g/mol | strunz = 4.JC.05 | system = Isometric | class = Diploidal (m{{overline|3}}) <br/>H–M Symbol (2/m {{overline|3}}) | symmetry = ''Pn''{{overline|3}} | unit cell = a = 15.984 Å; Z = 4 | color = Dark brown | habit = Cubic/octahedral crystals | twinning = | cleavage = | fracture = Conchoidal | tenacity = | mohs = {{frac|5|1|2}} - 6 | luster = sub-metallic | polish = | refractive = n = 2.2 | opticalprop = Isotropic | birefringence = | dispersion = | pleochroism = | fluorescence= | absorption = | streak = Yellow brown | gravity = 3.9 | density = | melt = | fusibility = | diagnostic = | solubility = | diaphaneity = Translucent to opaque | other = | references = <ref name=Webmin>[http://www.webmineral.com/data/Cafarsite.shtml Cafarsite Mineral Data from Webmineral]</ref><ref name=Mindat>[http://www.mindat.org/min-849.html Cafarsite on Mindat.org]</ref><ref name=HBM>[http://rruff.geo.arizona.edu/doclib/hom/cafarsite.pdf Handbook of Mineralogy]</ref> }} '''Cafarsite''' ({{chem|Ca|8|(|Ti,Fe|2+|,Fe|3+|,Mn)|6–7|(AsO|3|)|12}}·{{chem|4H|2|O}}) is a rare calcium iron arsenite mineral. Manganese and titanium occur with iron in the formula.
It was first described in 1966 for an occurrence in the Binn Valley, Valais, Switzerland. Its name is from the composition, ''ca''lcium, ''f''errum (iron), and ''ars''enic.<ref name=Mindat/><ref name=Webmin/><ref name=HBM/> It has also been reported from Piedmont, Italy and the Hemlo gold mine in the Thunder Bay District, Ontario, Canada.<ref name=HBM/><ref name=Mindat/>
==References== {{reflist}}
Category:Oxide minerals Category:Cubic minerals Category:Minerals in space group 201 Category:Minerals described in 1966
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