Telluronevskite Locality: Poruba pod Vihorlatom , Southern Vihorlat Mts, Košice Region , Slovakia ( Locality at mindat.org ) Size: 5.1 x 3.5 x 3.2 cm. This specimen is from the type and so far only locality for the species, and shows tiny black grains embedded in quartz. It is a good, rare reference specimen for this species - a bismuth tellurium selenide. — Photo: Robert M. Lavinsky · CC BY-SA 3.0
Telluronevskite
Telluronevskite is an IMA-recognized mineral species in the sulfide class, with the chemical formula Bi₃TeSe₂.
It crystallizes in the hexagonal crystal system (space group P-3m1). It is a member of the Tetradymite structural group.
Key properties: specific gravity 8.1; Black streak; Metallic. Anisotropism: Moderate. Bireflectance: Noticeable in oil, yellowish white to gray luster.
IMA symbol Tnvk, IMA status: approved, named in 1993.
Found in opal-quartz veinlets and as disseminated grains in ‘secondary quartzite’ that was formed by contact metamorphism or hydrothermal alteration of volcanic rocks.
It is found associated with Quartz, opal.
Alludes to the chemical relationship to nevskite, through substitution of tellurium for selenium.