| Реферат: | eng: Tamuraite, ideally Ir5Fe10S16, occurs as discrete phases (≤20 μm) in composite inclusions hosted by grains of osmium (≤0.5 mm across) rich in Ir, in association with other platinum‐group minerals in the River Ko deposit of the Sisim Placer Zone, southern Krasnoyarskiy Kray, Russia. In droplet‐like inclusions, tamuraite is typically intergrown with Rh‐rich pentlandite and Ir‐bearing members of the laurite–erlichmanite series (up to ~20 mol.% “IrS2”). Tamuraite is gray to brownish gray in reflected light. It is opaque, with a metallic luster. Its bireflectance is very weak to absent. It is nonpleochroic to slightly pleochroic (grayish to light brown tints). It appears to be very weakly anisotropic. The calculated density is 6.30 g∙cm−3. The results of six WDS analyses are Ir 29.30 (27.75–30.68), Rh 9.57 (8.46–10.71), Pt 1.85 (1.43–2.10), Ru 0.05 (0.02–0.07), Os 0.06 (0.03–0.13), Fe 13.09 (12.38–13.74), Ni 12.18 (11.78–13.12), Cu 6.30 (6.06–6.56), Co 0.06 (0.04–0.07), S 27.23 (26.14–27.89), for a total of 99.69 wt %. This composition corresponds to (Ir2.87Rh1.75Pt0.18Ru0.01Os0.01)Σ4.82(Fe4.41Ni3.90Cu1.87Co0.02)Σ10.20S15.98, calculated based on a total of 31 atoms per formula unit. The general formula is (Ir,Rh)5(Fe,Ni,Cu)10S16. Results of synchrotron micro‐Laue diffraction studies indicate that tamuraite is trigonal. Its probable space group is R–3m (#166), and the unit‐cell parameters are a = 7.073(1) Å, c = 34.277(8) Å, V = 1485(1) Å3, and Z = 3. The c:a ratio is 4.8462. The strongest eight peaks in the X‐ray diffraction pattern [d in Å(hkl)(I)] are: 3.0106(2¯1 6)(100), 1.7699(4 ¯2 0)(71), 1.7583(2016)(65), 2.7994(205)(56), 2.9963(1010)(50), 5.7740(10 ¯2 )(45), 3.0534(20¯1)(43) and 2.4948(208)(38). The crystal structure is derivative of pentlandite and related to that of oberthürite and torryweiserite. Tamuraite crystallized from a residual melt enriched in S, Fe, Ni, Cu, and Rh; these elements were incompatible in the Os–Ir alloy that nucleated in lode zones of chromitites in the Lysanskiy layered complex, Eastern Sayans, Russia. The name honors Nobumichi Tamura, senior scientist at the Advanced Light Source of the Lawrence Berkeley National Laboratory, Berkeley, California.
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| Цитирование: | 1. Tolstykh, N.D.; Krivenko, A.P. On the composition of sulfides containing the platinum‐group elements. Zap. Vses. Mineral. O‐va 1994, 123, 41–49. (in Russian).
2. Barkov. A.Y.; Shvedov, G.I.; Nikiforov, A.A.; Martin, R.F. Platinum‐group minerals from Seyba, Eastern Sayans, Russia, and substitutions in the PGE‐rich pentlandite and ferhodsite series. Mineral. Mag. 2019, 83, 531–538, doi:10.1180/mgm.2019.16.
3. Barkov, A.Y.; Shvedov, G.I.; Martin, R.F. PGE–(REE–Ti)‐rich micrometer‐sized inclusions, mineral associations, compositional variations, and a potential lode source of platinum‐group minerals in the Sisim Placer Zone, Eastern Sayans, Russia. Minerals 2018, 8, 181, doi:10.3390/min8050181.
4. Bezzubtsev, V.V., Ed. The State Geological Map of the Russian Federation; Scale 1: 1 000 000 (the Third Generation); (Altai‐Sayan Series N‐46 Abakan; The explanation notes); The Ministry of Natural Resources and Environment of the Russian Federation, “RosNedra”, A.P. Karpinsky Russian Geological Research Institute (VSEGEI), and “Krasnoyarskgeolsyomka”: Saint Petersburg, Russia, 2008, pp. 391.
5. Nesterenko, G.V.; Zhmodik, S.M.; Belyanin, D.K.; Airiyants, E.V.; Karmanov, N.S. Micrometric inclusions in platinum‐group minerals from Gornaya Shoria, southern Siberia, Russia: Problems and genetic significance. Minerals 2019, 9, 327, doi:10.3390/min9050327.
6. Tamura, N. XMAS: A Versatile Tool for Analyzing Synchrotron X‐ray Microdiffraction Data. In Strain and Dislocation Gradients from Diffraction; Barabash, R., Ice, G., Eds.; Imperial College Press: London, UK, 2014, pp. 125–155.
7. Harris, D.C.; Cabri, L.J. Nomenclature of platinum‐group‐element alloys: Review and revision. Can. Mineral. 1991, 29, 231–237.
8. Knop, O.; Huang, C.‐H.; Reid, K.I.G.; Carlow, J.S. Chalcogenides of the transition elements. X. X‐ray, neutron, Mössbauer and magnetic studies of pentlandite and the π phases, π (Fe, Co, Ni, S), Co8MS8 and Fe4Ni4MS8 (M = Ru, Rh, Pd). J. Solid State Chem. 1976, 16, 97–116.
9. Barkov, A.Y.; Shvedov, G.I.; Silyanov, S.A.; Martin, R.F. Mineralogy of platinum‐group elements and gold in the ophiolite‐related placer of the River Bolshoy Khailyk, Western Sayans, Russia. Minerals 2018, 8, 247, doi:10.3390/min8060247.
10. Cabri, L.J.; Laflamme, J.H.G. Analyses of minerals containing platinum‐group elements. In Platinum‐Group Elements: Mineralogy, Geology, Recovery; Cabri, L.J., Ed.; Canadian Institute of Mining, Metallurgy and Petroleum (CIM): Montreal, QC, Canada, 1981; Special Volume 23, pp. 151–173.
11. Cabri, L.J., Ed. The Geology, Geochemistry, Mineralogy, Mineral Beneficiation of the Platinum‐Group Elements; Canadian Institute of Mining, Metallurgy and Petroleum, (CIM): Montreal, QC, Canada; 2002; Special Volume 54, p. 852.
12. Barkov, A.Y.; Fleet, M.E.; Martin, R.F.; Alapieti, T.T. Zoned sulfides and sulfarsenides of the platinum‐group elements from the Penikat layered complex, Finland. Can. Mineral. 2004, 42, 515–537, doi:10.2113/gscanmin.42.2.515.
13. Barkov, A.Y.; Tolstykh, N.D.; Shvedov, G.I.; Martin, R.F. Ophiolite‐related associations of platinum‐group minerals at Rudnaya, western Sayans, and Miass, southern Urals, Russia. Mineral. Mag. 2018, 82, 515–530; doi:10.1180/mgm.2018.82.
14. Cabri, L.J.; Harris, D.C.; Weiser, T.W. Mineralogy and distribution of platinum‐group mineral (PGM) placer deposits of the world. Explor. Min. Geol. 1996, 5, 73–167.
15. Barkov, A.Y.; Tolstykh, N.D.; Tamura, N.; Martin, R.F.; Ma, C. Kuvaevite, IMA 2020‐043, in: CNMNC Newsletter 58. Eur. J. Mineral. 2020, 32; doi.org/10.5194/ejm‐32‐645‐2020.
16. McDonald, A.M.; Kjarsgaard, I.; Cabri, L.J.; Ross, K.C., Ames, D.E., Bindi, L. & Good, D.J. Oberthürite, Rh3(Ni,Fe)32S32, and torryweiserite, Rh5Ni10S16, two new platinum‐group minerals from the Marathon deposit, Coldwell complex, Ontario, Canada: Descriptions, crystal chemical considerations and comments on the geochemistry of rhodium. Can. Mineral. 2021, 59, in press.
17. Jemetio, J.P.F.; Zhou, P.; Kleinke, H. Crystal structure, electronic structure and thermoelectric properties of Cu4Sn7S16. J. Alloys Compd. 2006, 417, 55–59, doi:10.1016/j.jallcom.2005.09.030.
18. McDonald, A.M.; Kjarsgaard, I.M.; Ross, K.C.; Ames, D.E.; Cabri, L.J.; Good, D.J. Oberthürite, IMA 2017‐072. CNMNC Newsletter No. 40, December 2017, p. 1579. Mineral. Mag. 2017, 81, 1577–1581.
19. Begizov, V.D.; Zavyalov, E.N. Ferhodsite (Fe,Rh,Ir,Ni,Cu,Co,Pt)9–xS8—A new mineral from the Nizhniy Tagil ultramafic complex. New Data Minerals 2016, 51, 8–11 (in Russian).
20. Yü, Z.; Hao, Z.; Wang, H.; Yin, S.; Cai, J. Jichengite, 3CuIr2S4∙(Ni,Fe)9S8, a new mineral, and its crystal structure. Acta Geol. Sin. 2011, 85, 1022–1027.
21. Glazunov, O.M. The Geochemistry and Petrology of the Gabbro‐Pyroxenite Formation of the Eastern Sayans; Nauka: Novosibirsk, Russia, 1975; p. 188. (in Russian)
22. Barkov, A.Y.; Thibault, Y.; Laajoki, K.V.O.; Melezhik, V.A.; Nilsson, L.P. Zoning and substitutions in Co–Ni–(Fe)–PGE sulfarsenides from the Mount General’skaya layered intrusion, Arctic Russia. Can. Mineral. 1999, 37, 127–142.
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