Editing Covellite (section)

{{Short description|Sulfide mineral}}
{{Infobox mineral
| name        = Covellite
| category    = [[Sulfide mineral]]
| boxwidth    = 
| boxbgcolor  = 
| image       = Covellite-252597.jpg
| imagesize   = 260px
| caption     = 
| formula     = CuS ([[copper monosulfide]])
| IMAsymbol   = Cv<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.CA.05a
| dana        = 02.08.12.01
| system      = [[Hexagonal crystal system|Hexagonal]] 
| class       = Dihexagonal dipyramidal (6/mmm) <br/>[[H–M Symbol]] (6/m 2/m 2/m)
| symmetry    = ''P''6<sub>3</sub>/mmc
| unit cell   = a = 3.7938&nbsp;Å, c = 16.341&nbsp;Å; Z&nbsp;=&nbsp;6
| color       = Indigo-blue or darker, commonly highly iridescent, brass-yellow to deep red
| habit       = Thin platy hexagonal crystals and rosettes also massive to granular.
| twinning    = 
| cleavage    = Perfect on {0001}
| fracture    = 
| tenacity    = Flexible 
| mohs        = 1.5–2
| luster      = Submetallic, inclining to resinous to dull
| refractive  = n<sub>ω</sub> = 1.450 n<sub>ε</sub> = 2.620
| opticalprop = Uniaxial (+)
| birefringence = 
| pleochroism = Marked, deep blue to pale blue
| streak      = Lead gray
| gravity     = 4.6–4.8
| melt        = 
| fusibility  = 2.5
| diagnostic  = 
| solubility  = 
| diaphaneity = Opaque
| other       = Micaceous cleavage
| references  = <ref name=Handbook>[http://rruff.geo.arizona.edu/doclib/hom/covellite.pdf Handbook of Mineralogy]</ref><ref name=Webmin>[http://webmineral.com/data/Covellite.shtml Webmineral data]</ref><ref name=Mindat>[http://www.mindat.org/min-1144.html Mindat.org]</ref>
}}

[[Image:Cp--Covellite.jpg|thumb|Covellite (gray) replacing and embaying chalcopyrite (light), polished section from Horn Silver Mine, San Francisco Mining District, [[Utah]]. Enlarged to 210 diameters. |alt=]]
'''Covellite''' (also known as '''covelline''') is a rare [[copper sulfide]] mineral with the [[chemical formula|formula]] CuS.<ref name="Mindat" /> This indigo blue [[mineral]] is commonly a secondary mineral in limited abundance and although it is not an important ore of copper itself, it is well known to mineral collectors.<ref name="Mindat" />

The mineral is generally found in zones of secondary enrichment ([[Supergene (geology)|supergene]]) of copper sulfide deposits. Commonly found as coatings on [[chalcocite]], [[chalcopyrite]], [[bornite]], [[enargite]], [[pyrite]], and other sulfides, it often occurs as pseudomorphic replacements of other minerals.<ref>{{Cite book|title=Chlorine Compounds-Advances in Research and Application|last=Q. Ashton Acton|date=2012|publisher=ScholarlyMedia LLC|isbn=9781481600040|oclc=1024280169}}</ref> The first records are from [[Mount Vesuvius]], formally named in 1832 after N. Covelli.<ref name=Mindat/>