Althausite

{{Short description|Magnesium phosphate mineral}}

{{Infobox mineral

| name = Althausite

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| image = Althausite-Hematite-Lizardite-704015.jpg

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| caption = Dark reddish brown, subhedral crystals of althausite in a serpentine-talc matrix with dark gray subhedral hematite crystals and greenish lizardite

| category = Phosphate minerals

| formula = Mg₂(PO₄)(OH,F)

|IMAsymbol=Ahs{{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}}

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| strunz = 8.BB.25

| system = Orthorhombic

| class = Dipyramidal (mmm)
H-M symbol: (2/m 2/m 2/m)

| symmetry = Pnma

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| references = {{Cite web|url=https://www.mineralienatlas.de/lexikon/index.php/MineralData?mineral=Althausite|title=Mineralienatlas - Fossilienatlas}}[http://www.mindat.org/min-148.html Mindat][http://webmineral.com/data/Althausite.shtml Webmineral data]

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Althausite is a relatively simple magnesium phosphate mineral with formula Mg₂(PO₄)(OH,F). It is very rare. Original occurrences are magnesite deposits among serpentinites. It is named after Egon Althaus (born 1933), a mineralogist at the University of Karlsruhe, Germany.Raade G. and Tysseland M. 1975: Althausite, a new mineral from Modum, Norway. Lithos, 8, 215-219http://www.handbookofmineralogy.org/pdfs/althausite.pdf Handbook of Mineralogy