Lenaite
Lenaite is an IMA-recognized mineral species in the sulfide class, with the chemical formula AgFeS₂.
It crystallizes in the tetragonal crystal system (space group I-42d). It is a member of the Chalcopyrite structural group.
Key properties: Mohs hardness 4–4.5; specific gravity 4.72; Black streak; Metallic luster.
IMA symbol Ln, IMA status: approved, named in 1994.
Found in goethite pseudomorphs after magnesian siderite, in quartz-siderite veins (Russia); in an epithermal gold-silver telluride vein deposit (Gies deposit, Montana).
It is found associated with Acanthite, stephanite, Ag-Hg amalgam, chalcopyrite, tetrahedrite, galena, goethite (Russia); hessite, imiterite, proustite, tetrahedrite, tennantite.
The name refers to its occurrence near the Lena River, Russia.