{{Short description|Phyllosilicate mineral in the serpentine subgroup}} {{Infobox mineral | name = Fraipontite | image = Fraipontite-sea52a.jpg | imagesize = 260px | alt = | caption = Pockets of minute pearly white fraipontite crystals with green smithsonite from Laurium, Greece (size: 1.4 x 1.0 x 0.9 cm) | category = Phyllosilicate minerals | group = Kaolinite-Serpentine group, serpentine subgroup | formula = {{chem2|(Zn,Al)3(Si,Al)2O5(OH)4}} | IMAsymbol = Fpt<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 = 9.ED.15 | system = Monoclinic | class = Domatic (m) <br/><small>(same H-M symbol)</small> | symmetry = ''Cm'' | unit cell = a = 5.34, b = 9.21 <br/>c = 14.12 [Å]; β = 93.2°; Z = 2 | color = Blueish, yellow white light green | colour = | habit = Fibrous to porcelaneous massive | twinning = | cleavage = | fracture = | tenacity = | mohs = 3.5 – 4 | luster = Silky | streak = White to pale green | diaphaneity = Opaque to translucent | gravity = 3.08 – 3.10 | density = | polish = | opticalprop = Biaxial (-) | refractive = n<sub>α</sub> = 1.620 n<sub>β</sub> = 1.624 n<sub>γ</sub> = 1.624 | birefringence = δ = 0.004 | pleochroism = | 2V = Measured: 15° to 20° | dispersion = | extinction = | length fast/slow = | fluorescence = | absorption = | melt = | fusibility = | diagnostic = | solubility = | impurities = | alteration = | other = | prop1 = | prop1text = | references = <ref name=Handbook/><ref name=Mindat/><ref name=Webmin/> }} '''Fraipontite''' is a zinc aluminium silicate mineral with a formula of {{chem2|(Zn,Al)3(Si,Al)2O5(OH)4}}.<ref name=Handbook>[http://rruff.geo.arizona.edu/doclib/hom/fraipontite.pdf Handbook of Mineralogy]</ref><ref name=Mindat>[http://www.mindat.org/min-1588.html Mindat.org]</ref>
It is a member of the kaolinite-serpentine mineral group and occurs as an oxidation product of zinc deposits. It occurs with smithsonite, gebhardite, willemite, cerussite and sauconite.<ref name=Handbook/>
It was first described in 1927 for an occurrence in Vieille Montagne, Verviers, Liège Province, Belgium.<ref name=Mindat/> It was named for Julien Jean Joseph Fraipont (1857–1910), and Charles de Fraipont, geologists of Liege, Belgium.<ref name=Webmin>[http://webmineral.com/data/Fraipontite.shtml Webmineral data for fraipontite]</ref> In addition to the type locality in Belgium, it has been reported from Tsumeb, Namibia; Laurium, Greece; Swaledale, North Yorkshire, England; the Silver Bill mine, Cochise County, Arizona, the Blanchard Mine, Socorro County, New Mexico and the Mohawk mine, San Bernardino County, California in the US; and from the Ojuela mine, Mapimi, Durango, Mexico.<ref name=Handbook/>
A synonym of the fraipontite is the zinalsite, which was reported in 1956 for an occurrence in Kazakhstan.<ref>[http://webmineral.com/data/Zinalsite.shtml Zinalsite on Webmineral]</ref><ref>[http://www.mindat.org/min-4404.html Zinalsite on Mindat]</ref>
==References== {{Reflist}}
==External links== {{Commons category-inline}}
{{Phyllosilicates}}
Category:Zinc minerals Category:Aluminium minerals Category:Serpentine subgroup Category:Monoclinic minerals Category:Minerals in space group 8 Category:Minerals described in 1927
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