Lipscombite

{{Short description|Phosphate mineral}} {{Infobox mineral | name = Lipscombite | boxwidth = | boxbgcolor = | image = Lipscombite sample.jpg | imagesize = | alt = | caption = Lipscombite: Small green crystals on quartz, Harvard Museum of Natural History | category = Phosphate minerals | formula = (Fe2+,Mn2+)(Fe3+)2(PO4)2(OH)2 | IMAsymbol = Lcb<ref>{{Cite journal|last=Warr|first=L.N.|date=2021|title=IMA–CNMNC approved mineral symbols|url=https://www.cambridge.org/core/journals/mineralogical-magazine/article/imacnmnc-approved-mineral-symbols/62311F45ED37831D78603C6E6B25EE0A|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|url-access=subscription}}</ref> | strunz = 8.BB.90 | dana = 41.10.02.01 | system = Tetragonal | class = Trapezohedral (422) (same H-M symbol) | symmetry = ''P''43212 | unit cell = a = 5.37, c = 12.81 [Å]; Z = 4 | molweight = 391.27 g/mol | color = Green gray, olive green, black. | colour = | habit = | twinning = | cleavage = | fracture = | tenacity = | mohs = | luster = | streak = | diaphaneity = | gravity = 3.68 | density = | polish = | opticalprop = Translucent to opaque | refractive = | birefringence = | pleochroism = | 2V = | dispersion = | extinction = | length fast/slow = | fluorescence = | absorption = | melt = | fusibility = | diagnostic = | solubility = | impurities = | alteration = | other = | prop1 = | prop1text = | references = <ref name=Mindat/><ref name=Webmin/> }}

thumb|right|Lipscombite: Small yellowish-green crystals, Lichtenberg Absetzer Mine dump, Ronneburg Uranium deposit, Gera, Thuringia, Germany thumb|right|Lipscombite: Small black crystals on dark background. Smithsonian National Museum of Natural History

'''Lipscombite''' (Fe2+,Mn2+)(Fe3+)2(PO4)2(OH)2<ref name=Mindat>[http://www.mindat.org/min-2412.html Lipscombite on Mindat]</ref><ref name=Webmin>[http://www.webmineral.com/data/Lipscombite.shtml Lipscombite data on WebMineral]</ref> is a green gray, olive green, or black. phosphate-based mineral containing iron, manganese, and iron phosphate.

Lipscombite is often formed at meteorite impact sites where its crystals are microscopically small, because crystal-forming conditions of pressure and temperature are brief.

In the Classification of non-silicate minerals lipscombite is in the lipscombite group, which also includes zinclipscombite. This group is within the non-silicate, category 8, anhydrous phosphates, lazulite supergroup.

==Discovery==

The mineral lipscombite was first made artificially and then found in nature. It was named after chemist William Lipscomb by the mineralogist John W. Gruner who first made it artificially.<ref name=Gheith1953/><ref name=Lipscomb2002/>

While investigating the stability relations of iron oxides small, black, shiny crystals were obtained when a spherical iron pressure-temperature vessel was contaminated with phosphorus.<ref name=Gheith1951/> The x-ray powder diffraction pattern was similar to lazulite, but unknown.

Gruner, a mineralogist at the University of Minnesota, gave Lipscomb, a chemistry professor there, the crystals for Lewis Katz and Lipscomb to determine the atomic structure using single-crystal x-ray diffraction. They initially called the mineral iron lazulite.<ref name=Katz1951/>

==References==

<ref name=Gheith1953>Gheith, M. A., [http://www.minsocam.org/ammin/AM38/AM38_612.pdf Lipscombite: A New Synthetic Iron Lazulite], ''Amer. Mineral., 38'', 612–628 (1953)</ref>

<ref name=Lipscomb2002>''Structures and Mechanisms: From Ashes to Enzymes'' (Acs Symposium Series) Gareth R. Eaton (Editor), Don C. Wiley (Editor), Oleg Jardetzky (Editor), American Chemical Society, Washington, DC (2002) (Autobiographical sketch by William Lipscomb, 14 pp. (Lipscombite: p. xvii). This chapter is online at [http://pubs.acs.org/isbn/9780841237360 pubs.acs.org]. Click PDF symbols at right.</ref>

<ref name=Gheith1951>Gheith, Mohamed A. Stability relations of ferric oxides and their hydrates. Lipscombite: a new synthetic iron lazulite. ''Thesis'' University of Minnesota (1951)</ref>

<ref name=Katz1951>Katz L., Lipscomb W. N. The crystal structure of iron lazulite, a synthetic mineral related to lazulite: ''Acta Crystallographica, 4'', 345–348 (1951).</ref>

</references>

==External links==

Gallery of [http://www.mindat.org/gallery.php?min=2412 lipscombite pictures] at mindat.org.

Category:Manganese(II) minerals Category:Phosphate minerals Category:Hydroxide minerals Category:Tetragonal minerals Category:Minerals in space group 96