Wulffite
A potassium-sodium-copper oxysulfate discovered in 2012 among Tolbachik's fumarole minerals.
Intro adapted from Wikipedia (CC BY-SA).
Wulffite is an IMA-recognized mineral species in the sulfate class, with the chemical formula K₃NaCu₄O₂(SO₄)₄.
It crystallizes in the orthorhombic crystal system (space group Pn2_1a).
Key properties: Mohs hardness 2.5; specific gravity 3.23; Light green streak; Vitreous luster; optically biaxial.
IMA symbol Wlf, IMA status: approved, named in 2013.
Occurs as sublimates at a fumarole as incrustations on the surface of basalt scoria or on tenorite or aphthitalite crusts.
It is found associated with Euchlorine, fedotovite, hematite, johillerite, fluoborite, langbeinite, calciolangbeinite, arcanite, krasheninnikovite, lammerite, lammerite-β, bradaczekite.
The mineral was named to honor Russian crystallographer Georgiy Viktorovich Wulff (1863-1925).