Thalhammerite, Pd9Ag2Bi2S4, a New Mineral from the Talnakh and Oktyabrsk Deposits, Noril’sk Region, Russia
AbstractThalhammerite, Pd9Ag2Bi2S4, is a new sulphide discovered in galena-pyrite-chalcopyrite and millerite-bornite-chalcopyrite vein-disseminated ores from the Komsomolsky mine of the Talnakh and Oktyabrsk deposits, Noril’sk region, Russia. It forms tiny inclusions (from a few μm up to about 40–50 μm) intergrown in galena, chalcopyrite, and also in bornite. Thalhammerite is brittle and has a metallic lustre. In plane-polarized light, thalhammerite is light yellow with weak bireflectance, weak pleochroism, in shades of slightly yellowish brown and weak anisotropy; it exhibits no internal reflections. Reflectance values of thalhammerite in air (R1, R2 in %) are: 41.9/43.0 at 470 nm, 43.9/45.1 at 546 nm, 44.9/46.1 at 589 nm, and 46.3/47.5 at 650 nm. Three spot analyses of thalhammerite give an average composition: Pd 52.61, Bi 22.21, Pb 3.92, Ag 14.37, S 7.69, and Se 0.10, total 100.90 wt %, corresponding to the empirical formula Pd8.46Ag2.28(Bi1.82Pb0.32)Σ2.14(S4.10Se0.02)Σ4.12 based on 17 atoms; the average of five analyses on synthetic thalhammerite is: Pd 55.10, Bi 24.99, Ag 12.75, and S 7.46, total 100.30 wt %, corresponding to Pd8.91Ag2.03Bi2.06S4.00. The density, calculated on the basis of the empirical formula, is 9.72 g/cm3. The mineral is tetragonal, space group I4/mmm, with a 8.0266(2), c 9.1531(2) Å, V 589.70(2) Å3 and Z = 2. The crystal structure was solved and refined from the single-crystal X-ray-diffraction data of synthetic Pd9Ag2Bi2S4. Thalhammerite has no exact structural analogues known in the mineral system; chemically, it is close to coldwellite (Pd3Ag2S) and kravtsovite (PdAg2S). The strongest lines in the X-ray powder diffraction pattern of synthetic thalhammerite [d in Å (I) (hkl)] are: 3.3428(24)(211), 2.8393(46)(220), 2.5685(21)(301), 2.4122(100)(222), 2.3245(61)(123), 2.2873(48)(004), 2.2201(29)(132), 2.0072(40)(400), 1.7481(23)(332), and 1.5085(30)(404). The mineral honours Associate Professor Oskar Thalhammer of the University of Leoben, Austria. View Full-Text
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Vymazalová, A.; Laufek, F.; Sluzhenikin, S.F.; Kozlov, V.V.; Stanley, C.J.; Plášil, J.; Zaccarini, F.; Garuti, G.; Bakker, R. Thalhammerite, Pd9Ag2Bi2S4, a New Mineral from the Talnakh and Oktyabrsk Deposits, Noril’sk Region, Russia. Minerals 2018, 8, 339.
Vymazalová A, Laufek F, Sluzhenikin SF, Kozlov VV, Stanley CJ, Plášil J, Zaccarini F, Garuti G, Bakker R. Thalhammerite, Pd9Ag2Bi2S4, a New Mineral from the Talnakh and Oktyabrsk Deposits, Noril’sk Region, Russia. Minerals. 2018; 8(8):339.Chicago/Turabian Style
Vymazalová, Anna; Laufek, František; Sluzhenikin, Sergey F.; Kozlov, Vladimir V.; Stanley, Chris J.; Plášil, Jakub; Zaccarini, Federica; Garuti, Giorgio; Bakker, Ronald. 2018. "Thalhammerite, Pd9Ag2Bi2S4, a New Mineral from the Talnakh and Oktyabrsk Deposits, Noril’sk Region, Russia." Minerals 8, no. 8: 339.
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