{{Short description|Sulfate mineral}} {{Infobox mineral | name = Devilline | category = Sulfate minerals | image = Devilline-t08-23b.jpg | caption = Devilline | formula = CaCu<sub>4</sub>(SO<sub>4</sub>)<sub>2</sub>(OH)<sub>6</sub>·3(H<sub>2</sub>O) | IMAsymbol = Dev<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 = 7.DD.30 | system = Monoclinic | class = Prismatic (2/m) <br /><small>(same H-M symbol)</small> | symmetry = ''P''2<sub>1</sub>/c | unit cell = a = 20.870, b = 6.135 <br />c = 22.91 [Å], β = 102.73° <br />V = 2,861.23 Å<sup>3</sup> | color = Green, blueish green; green in transmitted light | habit = Prismatic, lamellar, platy pseudohexagonal crystals | twinning = On {010} | cleavage = Perfect (001) distinct (110) and (101) | fracture = | tenacity = Brittle | mohs = 2.5 | luster = Vitreous, pearly | refractive = n<sub>α</sub>=1.585, n<sub>β</sub>=1.649, n<sub>γ</sub>=1.660 | opticalprop = biaxial negative | 2V = 42° | birefringence = δ=0.075 | pleochroism = Visible | streak = Light green | gravity = | density = Measured: 3.13 g/cm<sup>3</sup> Calculated: 3.084 g/cm<sup>3</sup> | melt = | fusibility = | diagnostic = | solubility = Insoluble in water and concentrated H<sub>2</sub>SO<sub>4</sub>. Completely soluble in HNO<sub>3</sub>. | diaphaneity = | other = | references = <ref>{{Cite web|url=http://www.mindat.org/min-1270.html|title = Devilline on Mindat}}</ref><ref>{{Cite web|url=https://webmineral.com/data/Devilline.shtml|title=Devilline Mineral Data – Webmineral}}</ref> }} '''Devilline''' is a sulfate mineral with the chemical formula CaCu<sub>4</sub>(SO<sub>4</sub>)<sub>2</sub>(OH)<sub>6</sub>·3H<sub>2</sub>O. The name originates from the French chemist's name, Henri Etienne Sainte-Claire Deville (1818–1881).
Devilline crystallizes in the monoclinic system.<ref>Back, M., and Mandrine, J. (2008) Fleischer's Glossary of Mineral Species 2008. 58 p. Mineralogical Record, Tuscan, Arizona</ref> Crystallographically, it contains three vectors of unequal lengths and two pairs of vectors are perpendicular while the other pair makes an angle other than 90°. Devilline is prismatic and belongs to the crystal class 2/m. This mineral belongs to the space group P 2<sub>1</sub>/c. Devilline is an anisotropic mineral, meaning that the mineral has different properties in different directions. Optically, this mineral is biaxial negative, meaning that it contains two optic axes. Devilline has a moderate mineral relief. Mineral relief refers to the way a mineral appears to stand out when viewed under polarized light and it is dependent on the mineral's index of refraction.
Devilline is a rare and unusual secondary mineral found in the oxidized portions of copper sulfide ore deposits.<ref name="HoM">{{cite web |last1=Anthony |first1=John W. |last2=Bideaux |first2=Richard A. |last3=Bladh |first3=Kenneth W. |last4=Nichols |first4=Monte C. |title=Devilline |url=https://www.handbookofmineralogy.org/pdfs/devilline.pdf |website=Handbook of Mineralogy |publisher=Mineral Data Publishing |access-date=28 December 2021 |date=2005}}</ref> Because Devilline occurs in such oxidation zones, this mineral often is of post-mining origin. Devilline is found in mines all around the world.
== Devilline group == Devilline group minerals are monoclinic sulfates.<ref>{{Cite book |first1=Malcolm E. |last1=Back |title=Fleischer's Glossary of Mineral Species |year=2014 |edition=11 |publisher=Mineralogical Record Inc. |pages=434 |location=Tucson AZ}}</ref>
{| class="wikitable" |- ! Mineral !! Chemical formulae !! Crystal system |- | Campigliaite || Cu<sub>4</sub>Mn<sup>2+</sup>(SO<sub>4</sub>)<sub>2</sub>(OH)<sub>6</sub>·4H<sub>2</sub>O || Monoclinic |- | Devilline || CaCu<sub>4</sub>(SO<sub>4</sub>)<sub>2</sub>(OH)<sub>6</sub>·3H<sub>2</sub>O || Monoclinic |- | Kobyashevite || Cu<sub>5</sub>(SO<sub>4</sub>)<sub>2</sub>(OH)<sub>6</sub>·4H<sub>2</sub>O || Triclinic |- | Ktenasite || Zn(Cu,Zn)<sub>4</sub>(SO<sub>4</sub>)<sub>2</sub>(OH)<sub>6</sub>·6H<sub>2</sub>O || Monoclinic |- | Lautenthalite || PbCu<sub>4</sub>(SO<sub>4</sub>)<sub>2</sub>(OH)<sub>6</sub>·3H<sub>2</sub>O || Monoclinic |- | Serpierite || Ca(Cu,Zn)<sub>4</sub>(SO<sub>4</sub>)<sub>2</sub>(OH)<sub>6</sub>·3H<sub>2</sub>O || Monoclinic |}
==References== {{Reflist}}
Category:Calcium minerals Category:Copper(II) minerals Category:Sulfate minerals Category:Monoclinic minerals Category:Minerals in space group 14
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