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from natural diamonds. It is shown that distribution of “amber” defects does not correlate with that of the Adefects; moreover, they appear anticorrelated. Available data suggest that although formation of the “amber” | from natural diamonds. It is shown that distribution of “amber” defects does not correlate with that of the Adefects; moreover, they appear anticorrelated. Available data suggest that although formation of the “amber” | ||
defects is related to deformation processes, it also requires presence of exotic set of point defects. | defects is related to deformation processes, it also requires presence of exotic set of point defects. | ||
− | <p>Keywords: Diamond, infra-red spectroscopy, “amber” defects.< | + | <p>Keywords: Diamond, infra-red spectroscopy, “amber” defects.<br> |
| Файл = Shiriaev2018-4_eng.pdf | | Файл = Shiriaev2018-4_eng.pdf | ||
| Приложения = | | Приложения = | ||
Строка 158: | Строка 158: | ||
| Название = A find of tungstenite-2H at the Kukhilal noble spinel magnesian-scarn deposit (South West Pamir, Tajikistan) | | Название = A find of tungstenite-2H at the Kukhilal noble spinel magnesian-scarn deposit (South West Pamir, Tajikistan) | ||
| Аннотация = Tungstenite-2H was found in magnesian scarns at the Kukhilal spinel deposit (a western slope of the Ishkashim Ridge, South West Pamir, Tajikistan). It forms aggregations of tabular crystals from 1.5 to 8 mm in size in a white forsterite rock with chrysotile, calcite, dolomite, clinochlore, apatite, brucite, talc, zircon, monazite-(Ce), barite, pyrrhotite, pyrite, galena, sphalerite and chalcopyrite. Tungstenite-2H is silver white, similar molybdenite. VHN 28 (ranges 25–29). A reflectance spectra are shown. Reflectance is moderate, it is higher in growth zones enriched with Mo. Microprobe analysis (total 6) (wt%): W 73.01–68.00; Mo 0.58–4.71; S 26.21–27.45, total 99.80–100.16. Empirical formula (calculated on the basis of 3 atoms) (W<sub>0.98–0.87</sub>Mo<sub>0.01–0.12</sub>)S<sub>2.01</sub>. X-ray powder data are given. The hexagonal cell parameters are: <i>a</i> = 3.161(1), <i>c</i> = 12.343(3) Å. Tungstenite-2H crystallized under strongly reducing conditions with high S<sup>2-</sup> activity. | | Аннотация = Tungstenite-2H was found in magnesian scarns at the Kukhilal spinel deposit (a western slope of the Ishkashim Ridge, South West Pamir, Tajikistan). It forms aggregations of tabular crystals from 1.5 to 8 mm in size in a white forsterite rock with chrysotile, calcite, dolomite, clinochlore, apatite, brucite, talc, zircon, monazite-(Ce), barite, pyrrhotite, pyrite, galena, sphalerite and chalcopyrite. Tungstenite-2H is silver white, similar molybdenite. VHN 28 (ranges 25–29). A reflectance spectra are shown. Reflectance is moderate, it is higher in growth zones enriched with Mo. Microprobe analysis (total 6) (wt%): W 73.01–68.00; Mo 0.58–4.71; S 26.21–27.45, total 99.80–100.16. Empirical formula (calculated on the basis of 3 atoms) (W<sub>0.98–0.87</sub>Mo<sub>0.01–0.12</sub>)S<sub>2.01</sub>. X-ray powder data are given. The hexagonal cell parameters are: <i>a</i> = 3.161(1), <i>c</i> = 12.343(3) Å. Tungstenite-2H crystallized under strongly reducing conditions with high S<sup>2-</sup> activity. | ||
− | <p>Keywords: tungstenite-2H, Kukhilal spinel deposit, South West Pamir, Tajikistan, magnesian scarns.< | + | <p>Keywords: tungstenite-2H, Kukhilal spinel deposit, South West Pamir, Tajikistan, magnesian scarns.<br> |
| Файл = Pautov2018-4_rus.pdf | | Файл = Pautov2018-4_rus.pdf | ||
| Приложения = | | Приложения = | ||
Строка 166: | Строка 166: | ||
| Аннотация = Greenockite, CdS (hex.), and otavite, CdCO<sub>3</sub>, have been found for the first time in the Darai-Pioz alkaline massif (Tadzhikistan). Greenockite (with Zn, ranges 3.3 – 3.8 wt. %) forms grains to 0.4 mm in galena aggregations from an aegirine-quartz-feldspar assemblage, in association with polylithionite, cesium-kupletskite, riebeckite-arfvedsonite series amphibole, turkestanite, and anglesite. Hexagonal cell dimensions are as follows: a = 4.171(2), c = 6.772(1) Å. Otavite occurs on a galena micro-vein contact with granulated quartz, as fine aggregations (~0.5 x 0.5 mm), on which Cd- bearing cerussite has developed (CdO 2.3 wt.%). The chemical composition of otavite is variable (mol. %): 77 – 87 CdCO<sub>3</sub>, 4 – 19 CaCO<sub>3</sub>, 4 – 9 PbCO<sub>3</sub>, 1 – 5 ZnCO<sub>3</sub>. Cd, and some trace elements were analysed in sphalerite from this massif; Cd ranges there from 0.12 to 3.65 wt. %. Minerals were investigated by microprobe with EDS and WDS, X-ray, and optical microscopy. A reflective spectrum is shown for greenockite. Possible methods of Zn and Cd differentiation are discussed. This may be the first identification of these minerals in alkaline massifs.<br> | | Аннотация = Greenockite, CdS (hex.), and otavite, CdCO<sub>3</sub>, have been found for the first time in the Darai-Pioz alkaline massif (Tadzhikistan). Greenockite (with Zn, ranges 3.3 – 3.8 wt. %) forms grains to 0.4 mm in galena aggregations from an aegirine-quartz-feldspar assemblage, in association with polylithionite, cesium-kupletskite, riebeckite-arfvedsonite series amphibole, turkestanite, and anglesite. Hexagonal cell dimensions are as follows: a = 4.171(2), c = 6.772(1) Å. Otavite occurs on a galena micro-vein contact with granulated quartz, as fine aggregations (~0.5 x 0.5 mm), on which Cd- bearing cerussite has developed (CdO 2.3 wt.%). The chemical composition of otavite is variable (mol. %): 77 – 87 CdCO<sub>3</sub>, 4 – 19 CaCO<sub>3</sub>, 4 – 9 PbCO<sub>3</sub>, 1 – 5 ZnCO<sub>3</sub>. Cd, and some trace elements were analysed in sphalerite from this massif; Cd ranges there from 0.12 to 3.65 wt. %. Minerals were investigated by microprobe with EDS and WDS, X-ray, and optical microscopy. A reflective spectrum is shown for greenockite. Possible methods of Zn and Cd differentiation are discussed. This may be the first identification of these minerals in alkaline massifs.<br> | ||
There are 5 tables, 7 drawings, and 56 references in the paper.<br> | There are 5 tables, 7 drawings, and 56 references in the paper.<br> | ||
− | <p>Keywords: cadmium, greenockite, otavite, cerussite cadmium-bearing, galena, sphalerite cadmium-bearing, Darai-Pioz alkaline massif.< | + | <p>Keywords: cadmium, greenockite, otavite, cerussite cadmium-bearing, galena, sphalerite cadmium-bearing, Darai-Pioz alkaline massif.<br> |
| Файл = Karpenko2018-4_rus.pdf | | Файл = Karpenko2018-4_rus.pdf | ||
| Приложения = | | Приложения = |
Текущая версия на 13:19, 25 декабря 2020
New Data on Minerals. 2018. Volume 52. 160 pages, 166 photos, drawings, and schemes.
Содержание
Summary
The journal contains a lot of new scientific information, including descriptions of new finds of minerals. So, in the southwestern Pamirs, the first rare herzenbergite and uranopolicraz in the myarolite granite pegmatites, and tungstenite-2H in magnesian skarns (Kuhilal), were discovered in Tajikistan for the first time in this type of deposit. For the first time in the alkaline massif Darai-Piez, cadmium minerals - greenokite and otavit - were found. This is probably the first discovery of cadmium minerals in alkaline rocks. New data on the content of Cd in sphalerite was obtained. Hypergenic copper minerals from Chukotka are described, among which spioncopite is the first in Russia. The features of rutile of potassium feldspar-quartz veins of volcanic rocks (Zap. Chukotka) are studied.
The results of an audit of titanium garnets from the collection of the Mineralogical Museum are presented in connection with changes in the nomenclature of this group of minerals. A brief report was made about phosphorus-containing olivine in the lavas of the last Tolbachinsky eruption, olivine of magmatic origin with a record phosphorus content was recorded. The first data of a systematic study of variations in the composition and morphology of cristobalite in the extrusive rocks of the Bezymyanny volcano (Kamchatka) are presented.
At the Tyrnyauz ore field (North Caucasus), the presence of macroscopically indistinguishable rock-forming minerals — wollastonite and ferrobustamite — was established, which requires the development of a methodology to determine the suitability of raw materials. An interesting hypergenic sulfate-arsenate mineralization was discovered and studied there (Sn-Bi-field Small Mukulan). In quartz veins of black siliceous schists, Auminzatau, V. Uzbekistan, vanadium grass-green poisonous was found and described. The results of IR microspectroscopy of the spatial distribution of “amber” defects in diamonds from placers of the northeast of the Siberian Platform are presented. The historical background of two samples of the Museum is revealed: porpecite and print of the seal made by Faberge. The chronology of scientific readings named after academician A.E. Fersman, authors and titles of scientific reports are presented, the time and place of the readings. One of the articles is dedicated to the memory of E.I. Semenov, a major specialist in the mineralogy of alkaline rocks and lithophilic rare metals, an employee of the museum.
This journal is of interest for mineralogists, geochemists, geologists, staff of natural history museums, collectors, and rocks aficionados.
Editorial Board
Editor in Chief: P.Yu. Plechov - Doctor of Geology and Mineralogy, Professor
Executive Editor: E.N. Matvienko - PhD in Geology and Mineralogy
Members of Editorial Board:
I.V. Pekov - Corresponding Member of the Russian Academy of Sciences, Doctor of Geology and Mineralogy
V.K. Garanin - Doctor of Geology and Mineralogy, Professor
M.I. Novgorodova - Doctor of Geology and Mineralogy, Professor
B.E. Borutsky - Doctor of Geology and Mineralogy
B.E Spiridonov - Doctor of Geology and Mineralogy
S.N. Nenasheva - PhD in Geology and Mineralogy
M.E. Generalov - PhD in Geology and Mineralogy
Yu.D. Gricenko - PhD in Geology and Mineralogy
L.A. Pautov - Senior Researcher
Editor, Design, Layout
E.V. Kronrod - PhD in Chemistry
Сontent
Issue 1 Revision articles and brief reports on the study of museum samples
Plechov P.Yu. (Editorial) Changes in the editorial policy of the journal "New data on minerals", p. 1-2
Gritsenko Yu.D. Titanium garnets collection of the A.E.Fersman Mineralogical Museum of the Russian Academy of Sciences, p. 3-5
Titanium garnets are widespread in many skarns and alkaline massifs. It was believed that shorlomite is much more widespread than morimotoite in the collection of the Fersman Mineralogical Museum RAS. We studied the collection of titanium and titanium-containing garnets of the Fersman Mineralogical Museum, which includes 22 samples from 19 different deposits. We did not find a single schorlomite among the studied samples. The ratio of morimotoite and shorlomite minals varies from 6.9 to 0.8 in Ti-andradite, and from 1.5 to 1.1 in titanium garnets. According to the nomenclature of the garnet supergroup, most analyzes of schorlomite in the literature correspond to the mineral species morimotoite. hus, morimotoite is more widespread than schorlomite, the reliable finds of which are much less than previously thought.
Keywords: titanium garnets, shorlomite, morimotoite, melanite, Fersman Mineralogical Museum of the Russian Academy of Sciences.
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Электронные приложения к статье : Gritsenko2018-1_supp_rus.xlsx
Pautov L.A., Mirakov M.A., Shodibekov M.A., Khvorov P.V. Finding of herzenbergite in the Vez-Dara granite miarolitic pegmatite at South West Pamir (Tajikistan), p. 6-14
Herzenbergite, SnS, was found in the near-miarolic complex of the Vez-Dara granite oligoclase-microcline pegmatite (vein #86) (South West Pamir, Tajikistan) in medium-grained K-feldspar-quartz rock. Minor minerals are biotite, schörl (graphics with quartz), spessartite-almandine garnet, albite. Herzenbergite occurs as irregular shape aggregates and veinlets up to 5 mm long, folded by lamellar grains 40–80 x 10–25 µm in size, partially replaced by “varlamovite”, in intergrowth with goethite, zircon, churchite- (Y), Sc-containing Mn-tantaloniobate. Herzenbergite is steel gray (in a fresh fracture), dark gray (on a weathered surface). In the reflected light is white; Rg = 49.9, Rp = 43.5% (560 nm). Bireflectance is weak (in air), and is clear (in immersion). Anisotropy with color effects in air is strong, in immersion is very strong. VHN 79–86 (at load 20 g). X-ray powder data are given. Unit cell parameters are a = 4.331(2), b = 11.195(3), c = 3.983(2) Ǻ. Chemical composition (microprobe, wt%): Sn 77.86–79.01; S 20.96–21.45, Pb, Cu, Sb, Fe are below the detection limit. The formula is Sn0.99–1.02S1.00. A direct crystallization under reducing conditions from an acidic solution enriched with Sn+2 at the low-temperature hydrothermal stage of pegmatite formation is assumed. Partial substitution with "varlamovite" aggregate can be caused both by the instability of SnS with an increase in the pH of solutions at the hypogenic stage, and as the result of supergene oxidation. It is the first find of herzenbergite in Tajikistan.
Keywords: herzenbergite, miarolitic pegmatite, South West Pamir, Tajikistan, Vez-Dara, "varlamovite".
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Shcherbakov V.D., Plechov P.Yu. P- bearing olivine from lava flow of 2012-2013 Tolbachik volcano eruption, p. 15-17
160 high-precision microprobe analyzes of olivine from lava and tephra of volcanic Tolbachik eruption are published in the paper. Hot-state lava and tephra were collected during the eruption. Phosphorus rich zones in olivine were formed during the skeletal growth in lava during flow on the surface.
Keywords: P-bearing olivine, high-precision microprobe analyses, Tolbachik, Kamchatka.
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Электронные приложения к статье : Sherbakov_Plechov2018-1_supp_eng.xlsx
Vlasov E.A., Nikolaev Yu.N., Apletalin A.V., Pustovalov V.Yu. Copper minerals from metamorphogenic veins of the headwaters of the river Ilirneivaem, Chukotka, p. 18-19
In the upper reaches of the Ilirneivey river, veins of epidote-calcite-prehnite composition with copper mineralization were found in altered andesites. The copper minerals are native copper, domeykite, chalcocite and spionkopite. The formation of veins is associated with the processes of low-grade metamorphism of the prehnite-pumpellyite facies, which captured the volcanites of the Tytylveem formation.
Keywords: Western Chukotka, native copper, low-grade metamorphism, prehnite-pumpellyite facies of metamorphism.
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Generalov M.E., Pautov L.A. Second Lieutenant Chernik Porpezite, p. 20-24
When studying the samples of porpezite transferred to the collection of the Mineralogical Museum by the G.P. Chernik in 1909, it was found that in addition to the proper porpezite (palladium gold of 600-700 probes), they contain native palladium and sulphide phases of Pd4S composition. It was also found out that placers, where platinum minerals were found at the end of the XIX century, are located not in Georgia, as indicated in the literature, but in Turkey, near the city of Artvin.
Keywords: porpezite, Fersman Mineralogical Museum of the RAS, G.P. Chernik, placers, Artvin.
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Generalov M.E. Faberge and Abraxas, p. 25-29
Impression on sealing wax of the seal made by Faberge Company tells about famous citizen of Russia and the United States, Boris Alexandrovich Bakhmetev, and about the connection of mysticism, philosophy, politics and art from ancient times to the early 20th century.
Keywords: seal, stonecurving, Faberge, Bakhmetev, history.
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Issue 2 Articles and short reports on the study of mineralogical objects
Pautov L.A., Shodibekov M.A., Mirakov M.A., Fayziev A.R., Khvorov P.V. Uranopolycrase (U,Y)(Ti,Nb)2O6 from the Museum miarolitic pegmatite in the area of the Kukhilal deposit (South West Pamir, Tajikistan)
Uranopolycrase (U,Y)(Ti,Nb)2O6 was found in the Museum miarolitic quartz-microcline-oligoclase pegmatite in the contours of the Kukhilal noble spinel deposit (South West Pamir) in a block semi-transparent, milky quartz of the near-miarolitic complex. It forms tabular grains of rectangular cross-section, rarely crystals up to 0.6 x 4 mm. Sometimes it growth together with Nb-containing rutile (Nb2O5 5.68 wt%), which outwardly is indistinguishable from the associating polycrase-(Y). The color is black, fracture is concoidal, lustre is pitchy. Fragile. Streak is light brown. In the reflected light is light gray, R ~ 20%, isotropic. Internal reflexes are rare reddish brown. VHN100 = 596. Chemical composition (microprobe, wt%): Nb2O5 8.75–13.27, Ta2O5 0.63–1.59, WO3 0.95–1.97, TiO2 31.00–34.39, UO2 31.59–41.41, ThO2 2.45–5.20, Y2O3 5.95–9.85, Ce2O3 0.00–0.77, Nd2O3 0.00–0.38, Dy2O3 0.99–2.12, Ho2O3 0.00–0.96, Er2O3 0.84–1.87, Yb2O3 0.73–1.97, FeO 0.00–0.32, MnO 0.00–0.32, CaO 0.00–0.69, total 98.16–101.32. Average formula is (calculated on the basis of О = 6 apfu): (U0.54Y0.26Th0.05Dy0.03Er0.03Yb0.03Ho0.01Nd0.01Ca0.02Fe0.01Mn0.01)1.00 (Ti1.63Nb0.34Ta0.02 W0.02)2.01O6. It is metamict. After the ignition (1000 °C, Ar flow), it gives X-ray diffraction pattern of the uranopolycrase with a minor amount of brannerite. Zones along the microcracks are replaced, presumably with the X-ray amorphous phase of the pyrochlore type (after ignition cell dimension is: a = 10.299 (4) Å). Minerals of the polycrase series are the main concentrators of uranium in the Museum pegmatite. This is the first find of uranopolycrase in Tajikistan.
Keywords: miarolitic pegmatite, South West Pamir, Museum pegmatite, Tajikistan, Kukhilal, uranopolycrase, polycrase-(Y), brannerite, metamictic.
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Ivanova Yu.A., Vlasov E.A. Rutile K-feldspar-quartz veins of headwaters of the river Dvoynaya, Western Chukotka
Numerous veins of calcite-adularia-quartz composition with titanite, epidote, allanite-(Ce), datolite, prehnite, chlorite, light mica, sulfides (pyrite, chalcopyrite, and molybdenite), wolframite, scheelite, and rutile are found in the volcanites of the Tytylveem formation. Impurities W6+, Nb5+, Fe3+, V3+, and Cr3+ were determined in rutile. A direct correlation was established between the concentration of W6+ and Nb5+ in rutile and the sum of trivalent cations, and the following isomorphic substitution schemes were proposed: 3Ti4+ = W6+ + 2Me3+; 2Ti4+ = Nb5+ + Me3+. In a number of analyzes of rutile, an excess of trivalent cations not compensated for by high-valence impurities is noted. The excess of trivalent cations is explained by the appearance of anionic vacancies in the structure according to the scheme 2Ti4+ + O2- = 2Me3++ [vac]. This assumption is confirmed by the oxygen deficiency in a number of crystal chemical formulas of rutile.
Keywords: Western Chukotka, rutile, impurities, isomorphism, isomorphic substitution schemes.
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Pavlova T.M. Academician A.E.Fersman scientific readings. History. Chronology.
The chronology of the scientific readings of Academician Fersman is given. The authors of the scientific reports and the topics are presented, as well as the time and place of the readings. The article contains 1 table, references (5 titles).
Keywords: scientific readings, A.E. Fersman, Mineralogical Museum of the Russian Academy of Sciences.
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Shchipalkina N.V., Kononov O.V., Pekov I.V., Koshlyakova N.N., Britvin S.N. Wollastonite and ferrobustite of the Tyrnyauz ore field (North Caucasus): chemical composition, relations and mineralogical-technological aspect
Samples previously identified as wollastonite, "ferrowollastonite", "Mn-wollastonite", parawolastonite, bustamite, and ferrobustite from different parts of the Tyrnyauz ore field (Kabardino-Balkaria, Northern Caucasus, Russia) were studied by electron probe microanalysis, infrared spectroscopy, powder and single-crystal radiography. It was found that two rock-forming minerals are presented at this site: wollastonite Ca3Si3O9 and ferrobustite Ca2Ca2FeCa[Si3O9]2, which are macroscopically indistinguishable from each other and can be found in the same mineral assemblages and capable of forming close intergrowths with each other, in which the boundaries between these minerals are always sharp. Wollastonite and ferrobustite can be easily identified by the method of infrared spectroscopy, and also differ in chemical composition. Thus, the FeO and MnO contents in wollastonite and ferrobustamite of the Tyrnyauz field vary in the following limits (wt.%): 0.0-1.2 and 0.1-1.1 (in total - from 0.1 to 2.3) in wollastonite, 7.4 - 10.2 and 1.3 - 3.7 (in the total - from 10.2 to 12.8) in ferrobustamite. Solid solutions between wollastonite and ferrobustamite were not fixed. The prevalence in the skarns of Tyrnyauz ferrobustamite seems to be a serious problem hampering the exploration and production of wollastonite, and makes it necessary to develop a special technique that makes it possible to distinguish conditioned wollastonite raw materials from mineral associations containing ferrobustite and unfit for practical use.
Keywords: wollastonite, ferrobustite, wollastonite concentrate "VOKSIL", pyroxenoid, infrared spectroscopy, technological mineralogy, Tyrnyauz.
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Ivanova D.A., Shcherbakov V.D., Plechov P.Yu., Nekrylov N.A., Davydova V.O., Turova M.A., Stepanov O.V. Cristobalite in extrusive rocks of Bezymianny volcano
We present the first data on the systematic study of compositional and morphological variability of cristobalite in extrusive rocks of Bezymianny volcano (Kamchatka). Andesites and dacites of all seven studied extrusive domes contain cristobalite, which content reaches up to 6 vol.%, and thus may be considered as rock-forming mineral. We distinguish 4 different morphological types of cristobalite – 1) isometric grains surrounded by pores with the characteristic fish-scale cracking; 2) the “prismatic” cristobalite grains in clusters; 3) “pea”-type grains in the matrix glass; 4) “feathery”-type crystals. There were not revealed any clear dependencies between the morphological type of cristobalite, its composition and the composition of host extrusive rocks. Content of minor elements in cristobalite (mainly Al and Na) is up 10 wt.% on an oxide basis. The main mechanism of their isomorphic substitution is Si4+→Al3++(Na+, K+), which can reflect the existence of a solid solution of cristobalite with isostructural to it carnegieite end-member. The entry of Ti (up to 0.27 wt.% of TiO2), Fe (up to 0.43 wt.% of FeO) and Ca (up to 0.15 wt.% of CaO) into the cristobalite structure is described. Cristobalite from extrusive rocks of Bezymianny volcano has the widest range of composition in comparison with all previously published analyses of this mineral.
Keywords: cristobalite, morphological and compositional variability, extrusive rocks, Bezymianny volcano, Kamchatka.
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Issue 3
Kasatkin A.V., Levitskiy V.V., Nestola F. Supergene minerals of Malyi Mukulan deposit (Tyrnyauz ore field, Northern Caucasus)
An interesting supergene sulfate-arsenate mineralization was discovered by us at the Malyi Mukulan Sn-Bi deposit, Tyrnyauz ore field, Kabardino-Balkaria, Northern Caucasus. A group of sulfates - bianchite, hexahydrite, gypsum, pickeringite, rozenite, cuprian siderotil, chalcanthite and epsomite, as well as arsenates of erythrite-kottigite series and pharmacosiderite were established and studied by EMPA, SXRD and PXRD.
Keywords: supergene minerals, sulfates, arsenates, kottigite, Malyi Mukulan deposit, Tyrnyauz, Kabardino-Balkaria.
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Gorelikova N.V., Portnov A.M., Taskaev V.I., Rassulov V.A., Chizhova I.A., Karimova O.V., Balashov F.V., Boyeva N.M. Vanadium dravite from the South East Uzbekistan
V-bearing magnesian tourmaline relate to dravite from South East Uzbekistan has been studied. This mineral is acicular, the colour is grassy. It is found out at quartz veins with the width up to 10 cm cutting Protorezoic black siliceous schists. Protorozoic schists have a high relation of К/Rb (800) that is typical for tholeitic basalts of oceanic type with a high content of Ti and V. The schists are also enriched in V and U (up to 50 ppm). V2O3 value in tourmaline varies and come to 3%. The negative correlation between V and Al has been established with methods correlation and R-factor analyses that indicates on the substitution Аl3+ by V3+ at the structure of tourmaline. The studied V-bearing tourmalines are characterized by a higher magnesiality (dravite variety), a low content of Fe2+ , Fe3+, Ti4+ and also of Аl3+, Са2+. Evidently, quartz-tourmaline veins are connected with the Hercinian granitoid magmatism attending numerous Au-Ag deposits of the South East Uzbekistan. Appearance of V in the quality a chromophor in metamorphic rocks is an indicator of old oceanic structures at the continents.
Keywords: Vanadium dravite, homovalent substitutions, photoluminescence, UV-Vis-NIR-spectroscopy, diffuse reflection, black chists, Protorozoic, indicator of oceanic structures, Auminzatau.
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Issue 4
Shiryaev A.A., Titkov S.V. Spatial distribution of “Amber” defects in diamond: results of IR mapping
Infra-red microspectroscopy was employed for investigation of spatial distribution of point defects in plates cut from natural diamonds. It is shown that distribution of “amber” defects does not correlate with that of the Adefects; moreover, they appear anticorrelated. Available data suggest that although formation of the “amber” defects is related to deformation processes, it also requires presence of exotic set of point defects.
Keywords: Diamond, infra-red spectroscopy, “amber” defects.
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Pautov L.A., Mirakov M.A., Shodibekov M.A., Fayziev A.R., Khvorov P.V., Makhmadsharif S. A find of tungstenite-2H at the Kukhilal noble spinel magnesian-scarn deposit (South West Pamir, Tajikistan)
Tungstenite-2H was found in magnesian scarns at the Kukhilal spinel deposit (a western slope of the Ishkashim Ridge, South West Pamir, Tajikistan). It forms aggregations of tabular crystals from 1.5 to 8 mm in size in a white forsterite rock with chrysotile, calcite, dolomite, clinochlore, apatite, brucite, talc, zircon, monazite-(Ce), barite, pyrrhotite, pyrite, galena, sphalerite and chalcopyrite. Tungstenite-2H is silver white, similar molybdenite. VHN 28 (ranges 25–29). A reflectance spectra are shown. Reflectance is moderate, it is higher in growth zones enriched with Mo. Microprobe analysis (total 6) (wt%): W 73.01–68.00; Mo 0.58–4.71; S 26.21–27.45, total 99.80–100.16. Empirical formula (calculated on the basis of 3 atoms) (W0.98–0.87Mo0.01–0.12)S2.01. X-ray powder data are given. The hexagonal cell parameters are: a = 3.161(1), c = 12.343(3) Å. Tungstenite-2H crystallized under strongly reducing conditions with high S2- activity.
Keywords: tungstenite-2H, Kukhilal spinel deposit, South West Pamir, Tajikistan, magnesian scarns.
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Karpenko V.Yu., Pautov L.A., Agakhanov A.A., Siidra O.I. On the cadmium mineralization in the Darai-Pioz alkaline massif
Greenockite, CdS (hex.), and otavite, CdCO3, have been found for the first time in the Darai-Pioz alkaline massif (Tadzhikistan). Greenockite (with Zn, ranges 3.3 – 3.8 wt. %) forms grains to 0.4 mm in galena aggregations from an aegirine-quartz-feldspar assemblage, in association with polylithionite, cesium-kupletskite, riebeckite-arfvedsonite series amphibole, turkestanite, and anglesite. Hexagonal cell dimensions are as follows: a = 4.171(2), c = 6.772(1) Å. Otavite occurs on a galena micro-vein contact with granulated quartz, as fine aggregations (~0.5 x 0.5 mm), on which Cd- bearing cerussite has developed (CdO 2.3 wt.%). The chemical composition of otavite is variable (mol. %): 77 – 87 CdCO3, 4 – 19 CaCO3, 4 – 9 PbCO3, 1 – 5 ZnCO3. Cd, and some trace elements were analysed in sphalerite from this massif; Cd ranges there from 0.12 to 3.65 wt. %. Minerals were investigated by microprobe with EDS and WDS, X-ray, and optical microscopy. A reflective spectrum is shown for greenockite. Possible methods of Zn and Cd differentiation are discussed. This may be the first identification of these minerals in alkaline massifs.
There are 5 tables, 7 drawings, and 56 references in the paper.
Keywords: cadmium, greenockite, otavite, cerussite cadmium-bearing, galena, sphalerite cadmium-bearing, Darai-Pioz alkaline massif.
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