{{infobox mineral | name = Ludlamite | image = Ludlamite-md87a.jpg | imagesize = 200px | alt = | caption = | category = Phosphate mineral | formula = {{chem2|(Fe,Mn,Mg)3(PO4)2*4H2O}} | IMAsymbol = Lud<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 = 8.CD.20 | dana = | system = Monoclinic | class = Prismatic (2/m) <br/><small>(same H-M symbol)</small> | symmetry = ''P2''<sub>1</sub>/a | unit cell = a = 10.541(5), b = 4.646(4) <br/>c = 9.324(5)&nbsp;[Å]; β = 100.52°; Z&nbsp;=&nbsp;2 | color = Apple-green to bright green | colour = | habit = Tabular crystals; massive, granular | twinning = | cleavage = Cleavage: perfect on {001}, indistinct on {100} | fracture = | tenacity = | mohs = 3.5 | luster = Vitreous, pearly on cleavage | streak = Pale greenish white | diaphaneity = Translucent | gravity = 3.12–3.19 | density = | polish = | opticalprop = Biaxial (+) | refractive = n<sub>α</sub> = 1.650 - 1.653 n<sub>β</sub> = 1.669 - 1.675 n<sub>γ</sub> = 1.688 - 1.697 | birefringence = δ = 0.038 - 0.044 | pleochroism = | 2V = Measured: 82° | dispersion = | extinction = | length fast/slow = | fluorescence = | absorption = | melt = | fusibility = | diagnostic = | solubility = | impurities = | references = <ref name=Mindat>[http://www.mindat.org/min-2452.html Mindat.org]</ref><ref name=Webmin>[http://www.webmineral.com/data/Ludlamite.shtml Webmineral.com]</ref><ref name=HBM>{{Cite web |url=http://www.handbookofmineralogy.com/pdfs/ludlamite.pdf |title=Handbook of Mineralogy |access-date=2011-06-05 |archive-date=2016-03-04 |archive-url=https://web.archive.org/web/20160304063034/http://www.handbookofmineralogy.com/pdfs/ludlamite.pdf |url-status=dead }}</ref> }}

'''Ludlamite''' is a rare phosphate mineral with chemical formula {{chem2|(Fe,Mn,Mg)3(PO4)2*4H2O}}. It was first described in 1877 for an occurrence in Wheal Jane mine in Cornwall, England and named for English mineralogist Henry Ludlam (1824–1880).

==Occurrence== It occurs in granite pegmatites and as a hydrothermal alteration product of earlier phosphate bearing minerals in a reducing environment.<ref name=HBM/> It occurs associated with whitlockite, vivianite, triploidite, triplite, triphylite, siderite, phosphoferrite, fairfieldite and apatite.<ref name=Mindat/>

==References== {{Reflist}}

==External links== {{commonscat-inline|Ludlamite|lcfirst=yes}}

Category:Iron minerals Category:Phosphate minerals Category:Tetrahydrate minerals Category:Monoclinic minerals Category:Minerals in space group 14 Category:Minerals described in 1877

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