{{infobox mineral | name = Spertiniite | boxwidth = | image = Spertiniite-93262.jpg | imagesize = 260px | alt = | caption = Spertiniite from Dzhezkazgan, Kazakhstan (size: 5 mm) | category = Oxide mineral | formula = Cu(OH)<sub>2</sub> | IMAsymbol = Sni<ref>{{cite journal |last=Warr|first=L. N. |year=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 = 97.56 g/mol | strunz = 4.FD.05 | dana = 6.2.4.1 | system = Orthorhombic | class = Pyramidal (mm2) <br/>H-M symbol: (mm2) | symmetry = ''C''mc2<sub>1</sub> | unit cell = a = 2.95 Å, b = 10.59 Å <br/>c = 5.27 Å; Z = 4 | color = Blue, blue-green | habit = Flat tabular crystals occurring in radial to botryoidal aggregates | twinning = | cleavage = None | fracture = | tenacity = Brittle | mohs = Soft | luster = Vitreous | streak = | diaphaneity = Transparent | gravity = 3.93 | density = | polish = | opticalprop = Biaxial | refractive = ''n''<sub>α</sub> = 1.720, ''n''<sub>β</sub>= n.d., ''n''<sub>γ</sub> = > 1.800 | birefringence = | pleochroism = Strong; X = colorless; Z = dark blue | 2V = | dispersion = | extinction = | length fast/slow = | fluorescence = | absorption = | melt = | fusibility = | diagnostic = | solubility = | impurities = | alteration = | other = Decomposes in hot water (synthetic) | references = <ref name=Mindat>[https://.mindat.org/min-3724.html Spertiniite on Mindat]</ref><ref name=HBM>[https://rruff.geo.arizona.edu/doclib/hom/spertiniite.pdf Spertiniite] in ''The Handbook of Mineralogy''</ref><ref name=Webmin>[https://webmineral.com/data/Spertiniite.shtml#.UFXq87IiZcg Spertiniite on Webmineral]</ref> }}
'''Spertiniite''' is a rare copper hydroxide mineral. Chemically, it is copper(II) hydroxide with the formula Cu(OH)<sub>2</sub>. It occurs as blue to blue-green tabular orthorhombic crystal aggregates in a secondary alkaline environment altering chalcocite. Associated minerals include chalcocite, atacamite, native copper, diopside, grossular, and vesuvianite.<ref name=HBM/>
==Discovery and occurrence== It was first described in 1981 for an occurrence in the Jeffrey Mine of the Johns-Manville mine, Val-des-Sources, Quebec. It was named for mine geologist Francesco Spertini (born 1937).<ref name="Mindat" /><ref name="HBM" /> In addition to the type locality, it has also been reported from Mont Saint-Hilaire, Quebec; Ely, White Pine County, Nevada; and Bisbee, Cochise County, Arizona. It has been reported from Dzhezkazgan, Kazakhstan; from slag at Juliushutte, Astfeld, Harz Mountains, Germany; and from Tsumeb, Namibia.<ref name=HBM/>
A 2006 study has produced evidence the blue mineral chrysocolla may be a microscopic mixture of spertiniite, amorphous silica and water.<ref>[http://www.slac.stanford.edu/cgi-wrap/getdoc/slac-pub-12232.pdf François Farges, Karim Benzerara, Gordon E. Brown, Jr.; ''Chrysocolla Redefined as Spertiniite''; SLAC-PUB-12232; 13th International Conference On X-Ray Absorption Fine Structure (XAFS13); July 9-14, 2006; Stanford, California]</ref><ref>[http://www.mindat.org/min-1040.html Chrysocolla on Mindat]</ref> thumb|left|Crystal structure of spertiniite ==References== {{Reflist}}
Category:Copper(II) minerals Category:Hydroxide minerals Category:Orthorhombic minerals Category:Minerals in space group 36