Outstanding specimen of the extremely rare mineral dwornikite from one of the only three known localities worldwide: Lipovskoe Deposit, Rezh District, Urals Region, Russian Federation. The mineral occurs as sharp yellow-greenish acicular crystals covering a great part of the matrix. — Photo: David Hospital · CC BY-SA 4.0
Dwornikite
Dwornikite is an IMA-recognized mineral species in the sulfate class, with the chemical formula Ni(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 3.357; [Vitreous.] luster.
IMA symbol Dwo, IMA status: approved, named in 1981.
Found in a vanadium sulfide deposit, probably by oxidation of associated bravoite.
It is found associated with Patronite, sulfur, retgersite, szomolnokite, “bitumen”.
The mineral was named to honor Edward J. Dwornik (1920–), Lunar geologist and mineralogist, U.S. Geological Survey, Washington, D.C., USA, who studied several vanadium deposits.