View source for Stephanite

{{For|the [[nanomaterial]]|Ag-Sb2S3}}{{infobox mineral 
| name = Stephanite
| category    = [[Sulfosalt mineral]]
|image  = Stephanite-oldeuro-119a.jpg
| caption = 
| formula     = Ag<sub>5</sub>SbS<sub>4</sub>
| IMAsymbol   = Sph<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.GB.10
| dana        = 03.02.04.01
| system      = [[Orthorhombic]]
| class       = Pyramidal (mm2) <br/>[[H-M symbol]]: (mm2)
| symmetry    = ''C''mc2<sub>1</sub>
| colour      = Lead grey to black
| color       = 
| habit       = Tabular, pseudo-hexagonal crystals; massive
| twinning    = Common on [110] repeated, forms pseudohexagonal groupings
| cleavage    = Imperfect on {010}, poor on {021} 
| fracture    = Subconchoidal
| tenacity    = Brittle
| mohs        = 2.0–2.5
| lustre      = Metallic
| streak      = Iron black
| diaphaneity = Opaque
| gravity     = 6.26
| density     = 
| polish      = 
| opticalprop = Anisotropic in polished section
| refractive  = 
| birefringence = 
| pleochroism = Very weak – white to pale pink
| 2V          = 
| dispersion  = 
| extinction  = 
| length fast/slow =
| fluorescence= 
| absorption  =
| melt        = 
| fusibility  = 
| diagnostic  = 
| solubility  = 
| other       = 
| alteration  = 
| references  = <ref name=Handbook>http://rruff.geo.arizona.edu/doclib/hom/stephanite.pdf Handbook of Mineralogy</ref><ref name=Webmin>http://webmineral.com/data/Stephanite.shtml Webmineral data</ref><ref name=Mindat>http://www.mindat.org/min-3764.html Mindat.org</ref>
}}
'''Stephanite''' is a [[silver]] [[antimony]] [[sulfosalt mineral]] with formula: [[silver|Ag]]<sub>5</sub>[[antimony|Sb]][[sulfur|S]]<sub>4</sub>. It is composed of 68.8% [[silver]], and sometimes is of importance as an ore of this metal.{{sfn|Spencer|1911|p=880}}

==History==
Under the name Schwarzerz it was mentioned by [[Georgius Agricola]] in 1546, and it has been variously known as "black silver ore" ([[German language|German]] ''Schwarzgultigerz''), brittle silver-ore (''Sprödglanzerz''), etc. The name stephanite was proposed by [[Wilhelm Karl Ritter von Haidinger|W Haidinger]] in 1845 in honour of the [[Archduke Stephen, Palatine of Hungary|Archduke of Austria Stephan Franz Victor]] of Habsburg-Lorena (1817–1867). French authors use [[François Sulpice Beudant|F. S. Beudant]]'s name psaturose (from the [[Greek language|Greek]] ''ψαθυρός'', fragile).{{sfn|Spencer|1911|p=880}}

==Properties==
It frequently occurs as well-formed crystals, which are [[orthorhombic]] and occasionally show indications of [[hemimorphism]]: they have the form of six-sided [[prism (geometry)|prism]]s or flat tables terminated by large [[basal plane]]s and often modified at the edges by numerous pyramid-planes. [[Crystal twinning|Twinning]] on the prism-planes is of frequent occurrence, giving rise to pseudo-hexagonal groups like those of [[aragonite]]. The colour is iron-black, and the lustre metallic and brilliant; on exposure to light, however, the crystals soon become dull.{{sfn|Spencer|1911|p=880}} Stephanite is an important ore of silver in some mining camps.

==Occurrence==
Stephanite occurs as a  late-stage mineral with other ores of silver in [[hydrothermal]] [[Vein (geology)|veins]].{{sfn|Spencer|1911|p=880}} Associated minerals include [[proustite]], [[acanthite]], native silver, [[tetrahedrite]], [[galena]], [[sphalerite]] and [[pyrite]].<ref name=Handbook/> Localities which have yielded good crystallized specimens are Freiberg and Gersdorf near Rosswein in [[Saxony]], [[Chañarcillo]] in [[Chile]], and exceptionally [[Cornwall]]. In the Comstock lode in [[Nevada]] massive stephanite and [[argentite]] are important ores of silver.

==See also==
* [[List of minerals]]
* [[List of minerals named after people]]

==References==
{{Reflist}}

{{Commons category}}

;Attribution
*{{1911|first=Leonard James |last=Spencer |wstitle=Stephanite |volume=15 |page=880}}

[[Category:Silver minerals]]
[[Category:Antimony minerals]]
[[Category:Sulfosalt minerals]]
[[Category:Orthorhombic minerals]]
[[Category:Glances]]
[[Category:Minerals in space group 36]]