Native tungsten from the Bol'shaya Pol'ya river valley and Mt Neroyka, Russia. (26th February 2021)

• Record Type: Journal Article
• Authors: Mills, Stuart J.; Kartashov, Pavel M.; Kampf, Anthony R.; Rumsey, Mike S.; Ma, Chi; Stanley, Chris J.; Spratt, John; Rossman, George R.; Novgorodova, Margarita I.
• Is Part Of: Mineralogical magazine. Volume 85:Number 1(2021)
• Page Start: 76
• Page End: 81
• Publication Date: 2021-02-26
• Subjects: tungsten, -- new mineral, -- Bol'shaya Pol'ya river valley, -- Prepolar Urals, -- Russia, -- Mt Neroyka, -- rock crystal, -- Ust–Puiva, -- Tyumenskaya Oblast', -- Russia; Mineralogy -- Periodicals; Mineralogy -- Great Britain -- Periodicals; 549.05
• DOI: 10.1180/mgm.2021.7
• Languages: English
• ISSNs: 0026-461X

Abstract

Abstract: Native tungsten (IMA2011-004), W, is officially described as a new mineral from gold placers in the Bol'shaya Pol'ya river valley, Prepolar Urals, Russia, associated with yttriaite-(Y) and from quartz veins in the Mt Neroyka rock-crystal field, Ust–Puiva, Tyumenskaya Oblast', Russia. Tungsten forms polycrystalline grains and masses, and rarely cubo-octahedra. It is silver white to steel grey in colour, with metallic lustre and grey streak. The calculated density is 19.226 g/cm 3 . The Vickers hardness (VHN25 ) is 571.45 kg/mm 2 . In plane polarised light, tungsten is white with a pale-yellow tint and optically isotropic. Electron microprobe analyses of Bol'shaya Pol'ya river valley material provided W 99.27, Mo 0.06, Mn 0.04, Fe 0.01, total 99.38 wt.%. The five strongest powder X-ray diffraction lines are [ d obs Å( I )( hkl )]: 2.2422(100)(110), 1.5835(25)(200), 1.2929(48)(211), 1.0010(23)(310) and 0.8457(24)(321). Tungsten is cubic, Im $\bar{3}$ m, a = 3.1648(4) Å, V = 31.69(4) Å 3 and Z = 2. Some additional occurrences of native tungsten and technogenic tungsten found in Nature are also described.