Hermannjahnite

{{Short description|Rare sulfate mineral}}

{{Infobox mineral

| name = Hermannjahnite

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| category = Sulfate

| formula = CuZn(SO₄)₂

| IMAsymbol = Hjh{{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}}

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| system = Monoclinic

| class = Prismatic (2/m)
(same H-M symbol)

| symmetry = P2₁/n

| unit cell = a = 4.81, b = 8.48,
c = 6.76 [Å], β = 93.04° (approximated)

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Hermannjahnite is a rare sulfate mineral with the relatively simple formula CuZn(SO₄)₂. It is one of many fumarolic minerals discovered on the Tolbachik volcano.Siidra, O.I., Nazarchuk, E.V., Agakhanov, A.A., Lukina, E.A., Vergasova, L.P., Filatov, S.K., Pekov, I.V., Karpov, G.A., and Yapaskurt, V.O., 2015. Hermannjahnite, IMA2015-050. CNMNC Newsletter No. 27, October 2015, 1225; Mineralogical Magazine79, 1229–1236{{cite web|url=http://www.mindat.org/loc-5602.html |title=Tolbachik volcano, Kamchatka Oblast', Far-Eastern Region, Russia - Mindat.org |website=Mindat.org |accessdate=2016-03-13}}