Berthierite

{{Short description|Sulfosalt mineral: FeSb2S4}} {{Distinguish|text=Berthierine, a phyllosilicate from the serpentine subgroup}} {{Infobox mineral | name = Berthierite | image = Berthierite-224182.jpg | alt = | caption = | category = | formula = {{Chem2|FeSb2S4}} | IMAsymbol=Btr<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 = | strunz = 2.HA.20 | dana = | system = Orthorhombic | class = Dipyramidal (mmm) <br/>H-M symbol: (2/m 2/m 2/m) | symmetry = ''Pnam'' | unit cell = | color = Steel grey | colour = | habit = | twinning = | cleavage = Poor/indistinct | fracture = | tenacity = | mohs = 2–3 | luster = Metallic | streak = | diaphaneity = Opaque | gravity = 4.64 | density = | polish = | opticalprop = | refractive = | birefringence = | pleochroism = | 2V = | dispersion = | extinction = | length fast/slow = | fluorescence = | absorption = | melt = | fusibility = | diagnostic = | solubility = | impurities = | alteration = | other = | prop1 = | prop1text = | references = | var1 = | var1text = | var2 = | var2text = | var3 = | var3text = | var4 = | var4text = | var5 = | var5text = | var6 = | var6text = }}

'''Berthierite''' is a mineral, a sulfide of iron and antimony with formula {{Chem2|FeSb2S4 (FeS*Sb2S3)}}. It is steel grey in colour with a metallic lustre, which an iridescent tarnish can cover. Because of its appearance, it is often mistaken for stibnite ({{Chem2|Sb2S3}}, an antimony trisulfide mineral, free of {{Chem2|Fe(2+)}} sulfide).

It was discovered in France in 1827 and named for the French chemist, Pierre Berthier (1782–1861).

Berthierine, an iron(II)-rich phyllosilicate from the serpentine subgroup, with as chemical formula {{Chem2|(Mg,Fe)3(Si2O5)(OH)4}}, was also named in honor of Pierre Berthier. The great similarity between the two names is a frequent source of confusion between these two very different mineral species.

== References == {{Reflist}}

== External links == {{Commons}} * [https://web.archive.org/web/20060219045156/http://mineral.galleries.com/minerals/sulfides/berthier/berthier.htm Mineral galleries] * [https://www.mindat.org/min-640.html Mindat] * [https://www.webmineral.com/data/Berthierite.shtml Webmineral]

Category:Iron(II) minerals Category:Antimony minerals Category:Sulfosalt minerals Category:Orthorhombic minerals Category:Minerals in space group 62 Category:Glances