# Madocite

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> Markdown URL: https://mediated.wiki/source/Madocite.md
> Source: https://en.wikipedia.org/wiki/Madocite
> Source revision: 1310543320
> License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/)

{{Infobox mineral
| name        = Madocite
| category    = [Sulfosalt mineral](/source/Sulfosalt_mineral)
| boxwidth    = 
| boxbgcolor  = 
| image       = 
| imagesize   = 
| caption     = 
| formula     = {{chem2|Pb17(Sb,As)16S41}}
| IMAsymbol   = Mdc<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.LB.30
| system      = [Orthorhombic](/source/Orthorhombic)
| class       = Pyramidal (mm2) <br/><small>(same [H-M symbol](/source/H-M_symbol))</small>
| symmetry    = ''Pb2a''
| unit cell   = a = 27.2&nbsp; Å, b = 34.1&nbsp;Å, <br/>c = 8.12&nbsp;Å; Z&nbsp;=&nbsp;4
| color       = Grayish black
| habit       = Elongated and striated crystals; massive
| twinning    = 
| cleavage    = {010} Perfect
| fracture    = Conchoidal
| tenacity    = 
| mohs  = 3.25
| luster      = Metallic
| refractive  = 
| opticalprop = 
| birefringence = 
| pleochroism = Strong, from white to gray
| streak      = Grayish black, shining
| gravity     = 5.98
| density     = 
| melt        = 
| fusibility  = 
| diagnostic  = 
| solubility  = 
| diaphaneity = Opaque
| other       = 
| references  = <ref>[https://www.mineralienatlas.de/lexikon/index.php/MineralData?mineral=Madocite Mineralienatlas]</ref><ref name=Mindat>[http://www.mindat.org/min-2517.html Mindat.org]</ref><ref>(1968) American Mineralogist, 53, 1421</ref><ref name=Webmin>[http://webmineral.com/data/Madocite.shtml Webmineral data]</ref><ref name=HBM>Anthony, J. W., Bideaux, R. A., Bladh, K. W., and Nichols, M. C. (1990) Handbook of Mineralogy: Volume 1: Elements, Sulfides, Sulfosalts. 306 p. http://rruff.geo.arizona.edu/doclib/hom/madocite.pdf {{Webarchive|url=https://web.archive.org/web/20080515200938/http://rruff.geo.arizona.edu/doclib/hom/madocite.pdf |date=2008-05-15 }}</ref>
}}
'''Madocite''' is a mineral with a chemical formula of {{chem2|Pb17(Sb,As)16S41}}. Madocite was named for the locality of discovery, [Madoc](/source/Madoc%2C_Ontario_(township)), [Ontario](/source/Ontario), [Canada](/source/Canada). It is found in the marbles of the [Precambrian](/source/Precambrian) Grenville Limestone.<ref name=HBM/>  It is [orthorhombic](/source/orthorhombic) (rectangular prism with a rectangular base) and in the point group ''mm2''. Its crystals are elongated and striated along [001] to a size of 1.5&nbsp;mm.

Madocite is anisotropic and classified as having high relief. It also displays strong pleochroism.<ref name=Webmin/>

Madocite is found in small clusters in [marble](/source/marble) pits (near Madoc, Ontario), and was originally categorized in the 1920s as an unidentified sulfosalt mineral in an assemblage of [pyrite](/source/pyrite), [sphalerite](/source/sphalerite), and [jamesonite](/source/jamesonite) in marble. Later research was done by [John L. Jambor](/source/John_Leslie_Jambor) in the 1960s who went to the site and collected samples of the assemblages.<ref>[http://www.corpusetampois.com/cse-guettardite.html History of discovery]</ref>

==References==
{{Reflist}}

Category:Antimony minerals
Category:Arsenic minerals
Category:Lead minerals
Category:Sulfosalt minerals
Category:Orthorhombic minerals

{{sulfide-mineral-stub}}

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Adapted from the Wikipedia article [Madocite](https://en.wikipedia.org/wiki/Madocite) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Madocite?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.