# Gratonite

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> Markdown URL: https://mediated.wiki/source/Gratonite.md
> Source: https://en.wikipedia.org/wiki/Gratonite
> Source revision: 1284995090
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{{Short description|Sulfosalt mineral}}
{{Distinguish|Graftonite}}
{{Infobox mineral
| name        = Gratonite
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| image       = Gratonite-20896.jpg
| imagesize   = 260px
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| caption     = Gratonite, Excelsior Mine, [Cerro de Pasco](/source/Cerro_de_Pasco), Peru, the [type locality](/source/type_locality_(geology)). 1.7 x 1.6 x 1.5 cm.
| category    = [Sulfosalt minerals](/source/Sulfosalt_minerals)
| formula     = Pb<sub>9</sub>As<sub>4</sub>S<sub>15</sub>
| IMAsymbol   = Gtn<ref>{{Cite journal|last=Warr|first=L.N.|date=2021|title=IMA–CNMNC approved mineral symbols|journal=[Mineralogical Magazine](/source/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>
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| strunz      = 2.JB.55
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| system      = [Trigonal](/source/Trigonal)
| class       = Ditrigonal pyramidal (3m) <br/><small>(same [H-M symbol](/source/H-M_symbol))</small>
| symmetry    = ''R3m''
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'''Gratonite''' is a lead-arsenic sulfosalt mineral, with the chemical composition Pb<sub>9</sub>As<sub>4</sub>S<sub>15</sub>. It is considered a low-temperature dimorph of jordanite. Gratonite was discovered in 1939 at the Excelsior Mine,  [Cerro de Pasco](/source/Cerro_de_Pasco), [Peru](/source/Peru). <ref>{{Cite journal |last=Palache, C. and Fisher, D.J. |date=1940 |title=Gratonite - A new mineral from Cerro de Pasco |journal=[American Mineralogist](/source/American_Mineralogist)|volume=25 |pages=255-265}}</ref> It is named in honor of geologist [L. C. Graton](/source/Louis_Caryl_Graton) (1880–1970), who had a long-standing association with the Cerro de Pasco mines. The other location where it is found is the [Rio Tinto](/source/Rio_Tinto_(corporation)) mine, Minas de Riotinto (Huelva), Spain. The crystals are very similar to those from Cerro de Pasco.<ref>{{Cite book |last=Calvo Rebollar |first=Miguel |title=Minerales y Minas de España. Vol. II. Sulfuros y sulfosales. |publisher=Museo de Ciencias Naturales de Alava. |year=2003 |isbn=978-84-7821-543-0 |location=Vitoria, Spain |pages=590-591 |language=es |trans-title=Minerals and mines of Spain}}</ref>

==References==
{{Reflist}}

==External links==
*[http://rruff.geo.arizona.edu/doclib/hom/gratonite.pdf Mineral Data Publishing]
*[http://webmineral.com/data/Gratonite.shtml Webmineral]
*[http://www.mindat.org/min-1741.html Mindat]

{{Commons}}

Category:Lead minerals
Category:Arsenic minerals
Category:Sulfide minerals
Category:Trigonal minerals
Category:Minerals in space group 160

{{sulfide-mineral-stub}}

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