Dravertite
Dravertite is an IMA-recognized mineral species in the sulfate class, with the chemical formula CuMg(SO₄)₂.
It crystallizes in the monoclinic crystal system (space group P2_1/n). It is a member of the Zinkosite structural group.
Key properties: Mohs hardness 3.5; specific gravity 3.508; White streak; Vitreous luster; optically biaxial.
IMA symbol Dra, IMA status: approved, named in 2014.
Forms sublimates around active fumaroles.
It is found associated with Dolerophanite, euchlorine, tenorite, hematite, langbeinite, steklite, fedotovite, wulffite, anhydrite, anglesite (Arsenatnaya fumarole); euchlorine.
The mineral was named to honor the Russian mineralogist and geologist Petr Lyudovikovich Dravert (1879-1945) for his significant contribution to the mineralogy of Siberia.