Pokhodyashinite
Pokhodyashinite is an IMA-recognized mineral species in the sulfosalt class, with the chemical formula CuTlSb₂(Sb₁₋ₓTlₓ)AsS₇₋ₓ (0.2 < x < 0.5).
It crystallizes in the monoclinic crystal system (space group P-1).
Key properties: Mohs hardness 2; specific gravity 5.169; Black streak; Metallic luster.
IMA symbol Pok, IMA status: approved, named in 2020.
Found in mineralized carbonate breccia altered by the interaction between post-magmatic hydrothermal solutions and carbonate rocks.
It is found associated with Orpiment, pyrite, realgar, baryte, clinochlore, As-bearing fluorapatite, harmotome, prehnite, native gold, a rich spectrum of sulfosalts, calcite.
The mineral was named to honor Maxim Mikhailovitch Pokhodyashin (1708-1780), a pioneer of mining engineering and smelting works in the Northern Urals.