Several very very small single crystals of the very rare mineral selenium mineral dzharkenite (FeSe2) from the type locality: Suluchekinskoye Se-U Deposit, Dzharkenskaya, Almaty Province, Kazakhstan. — Photo: David Hospital · CC BY-SA 4.0
Dzharkenite
The isometric form of iron diselenide (FeSe₂), precipitated under reducing conditions — the cubic polymorph of ferroselite.
Intro adapted from Wikipedia (CC BY-SA).
Dzharkenite is an IMA-recognized mineral species in the sulfide class, with the chemical formula FeSe₂.
It crystallizes in the cubic crystal system (space group Pa3). It is a member of the Pyrite structural group.
Key properties: specific gravity 7.349; Black streak; Metallic to adamantine luster.
IMA symbol Dzh, IMA status: approved, named in 1993.
Found in Se–U ores in quartz-sandstone (Seluchekinskoye deposit, Kazakhstan); in a massive sulfide deposit (Zapadno-Ozernoe deposit, Russia).
It is found associated with Ferroselite, goethite (Seluchekinskoye deposit, Kazakhstan); pyrite, galena, tetrahedrite, metacinnabar, tiemannite, sulfur, gold.
The name refers to the Dzharkenskaya depression, within which the Seluchekinskoye deposit occurs.