Microinclusions of two extremely rare palladium-platinum minerals, sobolevskite and insizwaite, from the famous locality of Norilsk (Oktyabr'skoye Deposit, Putoran Plateau, Eastern Siberia, Russian Federation) in a matrix of cubanite-pentlandite-chalcopyrite in a polished specimen, that was analysed. — Photo: David Hospital · CC BY-SA 4.0
Insizwaite
Insizwaite is an IMA-recognized mineral species in the sulfide class, with the chemical formula PtBi₂.
It crystallizes in the cubic crystal system (space group Pa3). It is a member of the Pyrite structural group.
Key properties: specific gravity 12.8; Metallic. R: (400) 55.7, (420) 56.4, (440) 57.2, (460) 57.8, (480) 58.4, (500) 58.8, (520) 59.2, (540) 59.5 luster.
IMA symbol Isw, IMA status: approved, named in 1971.
Of hydrothermal origin, in a vein cutting massive pyrrhotite ore (Insizwa deposit, South Africa); in Cu–Ni sulfide ore (Sudbury, Canada).
It is found associated with Pentlandite, cubanite, hessite, altaite, argentopentlandite, chalcopyrite, mackinawite, niggliite, froodite, parkerite, galena, sphalerite, magnetite.
The name refers to the Insizwa deposit, South Africa, where it was discovered.