{{Short description|Mineral}} {{Infobox mineral | name = Gilalite | category = Silicate mineral | image = gilalite.jpg | imagesize = 260px | caption = Blue Gilalite crystals | formula = Cu<sub>5</sub>Si<sub>6</sub>O<sub>17</sub>·7(H<sub>2</sub>O) | IMAsymbol = Gil<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 = 884.3 g/mol | strunz = 9.HE.05 | system = Monoclinic <br/>Unknown space group | symmetry = | unit cell = a = 13.38, b = 19.16 <br/>c = 9.026 [Å]; β ≈ 90°; Z = 4 | color = Blue green, green | habit = Raidiating fibrous in spherules | twinning = | cleavage = | fracture = | tenacity = Waxy or gummy | mohs = 2 | luster = Nonmetallic | refractive = n<sub>α</sub>= 1.560 n<sub>β</sub>=1.635 n<sub>Ύ</sub>= 1.635 | opticalprop = Biaxial (-) | birefringence = δ = 0.075 | pleochroism = | streak = Light green | gravity = 2.72 | density = | melt = | fusibility = | diagnostic = | solubility = | diaphaneity = Translucent | other = | references = <ref>[http://www.wolframalpha.com/entities/minerals/gilalite/it/y5/04/ gilalite - Wolfram Alpha]</ref><ref name=HBM>[http://rruff.geo.arizona.edu/doclib/hom/gilalite.pdf Handbook of Mineralogy]</ref><ref name=Mindat>[http://www.mindat.org/min-1691.html Gilalite: Gilalite mineral information, Mindat.org]</ref> }}
'''Gilalite''' is a copper silicate mineral with chemical composition of Cu<sub>5</sub>Si<sub>6</sub>O<sub>17</sub>·7(H<sub>2</sub>O).<ref name=Mindat/>
It occurs as a retrograde metamorphic phase in a calc-silicate and sulfide skarn deposit. It occurs as fracture fillings and incrustations associated with diopside crystals.<ref name=HBM/> It is commonly found in the form of spherules of radial fibers. thumb|left|Gilalite inclusions within a quartz crystal from Juazeiro do Norte, Ceara State, Brazil (size: 7.1 x 4.7 x 2.7 cm) It was first described for an occurrence in the Christmas porphyry copper mine in Gila County, Arizona in 1980 along with the mineral apachite.<ref>F.P. Cesbron and S.A. Williams; March 1980;"Apachite and gilalite, two new copper silicates from Christmas, Arizona" Mineralogical Magazine, Vol. 43, pp. 639-41</ref> It derives its name from this locality. It has also been reported from the Goodsprings District, Clark County, Nevada; Juazeiro do Norte, Ceara State, Brazil and a slag area in Lavrion District, Attica, Greece.<ref name=Mindat/>
==References== {{Reflist}}
Category:Copper(II) minerals Category:Unclassified silicates Category:Monoclinic minerals
{{silicate-mineral-stub}}