Outstanding white crystals of the rare Zn sulphate mineral gunningite from the famous Bisbee deposit in Arizona (Bisbee, Warren District, Mule Mountains, Cochise County, Arizona, United States of America). Ex Vandenbroucke Museum collection from Waregem, Belgium. — Photo: David Hospital · CC BY-SA 4.0
Gunningite
A zinc-manganese sulfate monohydrate of the kieserite group, honoring Canadian geologist Henry Gunning.
Intro adapted from Wikipedia (CC BY-SA).
Gunningite is an IMA-recognized mineral species in the sulfate class, with the chemical formula Zn(SO₄)·H₂O.
It crystallizes in the monoclinic crystal system (space group C2/c). It is a member of the Kieserite structural group.
Key properties: Mohs hardness 2.5; specific gravity 3.195; White streak; Vitreous luster; refractive index 1.592; optically biaxial.
IMA symbol Gnn, IMA status: approved, named in 1962.
Of rare occurrence in dry areas of the oxidized portions of sphalerite-bearing deposits; occurs also as a post-mining efflorescence on museum specimens.
It is found associated with Sphalerite, scorodite, gypsum, pharmacosiderite, jarosite, arsenopyrite, “limonite” (Keno Hill–Galena Hill district, Canada); woodruffite.
The mineral was named to honor Dr. Henry Cecil Gunning (1901–1991), Geological Survey of Canada and Professor of Geology, University of British Columbia, Vancouver, Canada.