Vol 148, No 4 (2019)

General section
Pecularites of granite sistems including rare-metal pegmatites
Beskin S.M., Marin Y.B.
Abstract

There are usually two generations of granitic pegmatites revealed in most of rare-metal pegmatite fields: beryl-bearing ones, often with tantalum-niobate, muscovite, inseparable from vein-shaped granite leucogranite complex, and sodium-lithium (Li, Ta, Cs, Be, Sn) pegmatites (or LCT-pegmatites), which are subdivided into «complex rare-metal» ones, with the pegmatite zonation and the major mineralization (large crystals of spodumene, tantalates, beryl, cassiterite, pollucite, petalite, amblygonite) in central parts of their body (Koktogay, Bernick Lake, Bikita, Karibib, Varutresk, Vishnyakovskoye, etc.), and «albite-spodumene» ones, composing numerous extensive pegmatite dykes without zoning, grouping in their fields as long as up to 10—15 km and more (Kings Mountain, Zavitinskoye, Goltsovoye, Kolmozero, Polmos Tundras, Tastygskoye, etc.). In some cases (Zavitinskoye, Vasin-Mylk, Shuckbjul), there are established complex rare-metal pegmatites occurring in «heads» of conveying dykes of «albite-spodumene pegmatites». The search of «parent granites» for «albite-spodumene pegmatites» is meaningless, because they are not pegmatites, but granites, although special ones (in fact, they are spodumene granites of the alakhinsky type). The terminological, as it seems to be, readjustment: «granite, not pegmatite», has its scientific (a) and prognostic (b) consequences. Firstly, there is resolving (a) the problem of parent granites, objections to the pegmatite status of «albite-spodumene pegmatites» become removed. This type of pegmatites occupies in history of magmatism over some pegmatite-bearing areas its independent, spodumene-rare-metal-granite stage, concluded by formation of their own — true — complex pegmatites. And secondly (b): it may be assumed that under such complex pegmatite fields as Koktogay, Bernick Lake, Bikita, Karibib, Vishnyakovskoye, there are occurring series of dikes of spodumene-rare-metal granites (i. e., Li ore deposits), which are differentiates of complex pegmatites.

Zapiski RMO (Proceedings of the Russian Mineralogical Society). 2019;148(4):1-16
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Niz'yavrski alkaline massif: age, isotopic- geochemical characteristics and rare-metal mineralizetion
Petrovskiy M.N.
Abstract

The Nizʼyavrski alkaline massif includes the rocks of two intrusive phases: (1) alkaline syenites and (2) alkaline quartz syenites. The crystallization age of the latter determined by the U-Pb method for zircon is 2656 ± 3 Ma. According to isotopic (Rb-Sr and Sm-Nd) data, the rocks of the massif have a mantle origin. It is suggested that the source of their melts, as well as the source of melts for other Neoarchean alkaline intrusions of the Kola province belonging to the association of alkaline gabbro, nepheline syenites, alkaline syenites, and granosyenite, was the BSE mantle reservoir. Rocks of the massif contain Ta-Nb mineralization represented by pyrochlore, which distinguishes the studied intrusion from the other Neoarchean alkaline magmatic bodies of the province.

Zapiski RMO (Proceedings of the Russian Mineralogical Society). 2019;148(4):17-29
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Forms of occurrence and micro-nano ensambles of gold as indicators of formation conditions, spatial distribution, and type of orogenic deposits in Uzbekistan (South Tien Shan)
Koneev R.I., Khalmatov R.A., Krivosheeva A.N.
Abstract

Gold ore deposits of Uzbekistan are confined to the South Tien Shan orogenic belt. They are located in black shales (Muruntau, Amantaytau, Daugyztau), terrigenous sedimentary (Kokpatas), volcanic (Balpantau), and intrusive (Zarmitan, Guzhumsai) rocks. Their age is 280—290 Ma and coincides with the age of post-collision granitoid magmatism. The deposits form Kyzylkum and Nurata mining districts. Gold forms micro-nanoparticles and is incorporated into diversified compounds with Bi, Sb, As, Te, Se, S, Ag, Hg in primary quartz-sulfide and sulfide ores. Seven mineral and geochemical types of ores are recognized: Au—W with scheelite and molybdenite; Au—Bi—Te with maldonite, tellurides, bismuth sulpho-tellurides; Au—As with pyrite, arsenopyrite, Ni—Co minerals; Au—Ag—Te with calaverite, petzite, hessite, etc.; Au—Ag—Se with fichesserite, acanthite, freibergite, agvilarite, petrovskite, etc.; Au—Sb—Ag with aurostibite, boulangerite, burnonite, cincenite, chalcostibite, tetrahedrite, etc.; Au—Hg with cinnabar, consbergite, Hg-bearing native gold. Recoverable resources are determined by 2—3 types of ores. Three main types of gold deposits are proposed on the base of outlined mineralogical and geochemical types: Au—W—Bi—Te (Muruntau, Myutenbay, Zarmitan); Au—As—Sb—Ag (Amantaytau, Kokpatas, Daugyztau); Au—Ag—Sb—Se (Kosmanachi, Okzhetpes). The emphasis on the nanomineral approach in the study of gold, its compounds, and micro-nano ensembles increases the efficiency of searching, typifying and evaluating the prospects of hidden mineralization, and is favorable to determine the conditions of formation and technological properties of gold ores.

Zapiski RMO (Proceedings of the Russian Mineralogical Society). 2019;148(4):30-45
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History of mineralogy, crystallography and petrology
Several dates from the history of crystallography
Voytekhovsky Y.L.
Abstract

The article is devoted to significant dates from the history of crystallography, celebrated in 2019. They are mainly associated with the publication of fundamental scientific works (N. Stenon, M. V. Lomonosov, A. Bravais, E. Mallard, L. Sohncke, H. Heesch) and reflect the steady development of crystallography. On the other hand, they show failed discoveries. In particular, the idea of antisymmetry by H. Heesch is already contained in the bud by A. Bravais. It could be obtained by comparing his «direct and inverse half-forms» of crystal polyhedron. The possibility of such unexpected associations is due to the high degree of mathematization of modern crystallography.

Zapiski RMO (Proceedings of the Russian Mineralogical Society). 2019;148(4):46-52
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Geological heritage of M. V. Fishman
Pystin A.M.
Abstract

The article is dedicated to the memory of the well-known geologist, Doctor of Geological and Mineralogical Sciences, Professor, Honored Scientist of the RSFSR and the Komi ASSR, Chairman of the Syktyvkar Branch of the Russian Mineralogical Society, Director of the Institute of Geology of the Komi SC UrD RAS Mark V. Fishman (1919—2003). M. Fishman worked at the Institute of Geology (until 1958 — at the Department of Geology) from 1948 and for nearly a quarter of a century (from 1961 to 1985) headed the Institute. It was under his leadership that the main research directions of the Institute were formed and basic scientific and auxiliary laboratories were established. M. Fishman was not only a successful leader, but also an eminent scientist who made a huge contribution to the knowledge of the geological structure and history of the geological development of the European Northeast. The results of his scientific activity have largely determined the direction of geological research in this vast territory, have retained their importance for many decades, and to this day remain an example of an outstanding scientific achievement.

Zapiski RMO (Proceedings of the Russian Mineralogical Society). 2019;148(4):53-60
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Minerals and parageneses of minerals
Сhevkinite-(Се) and perrierite-(Се) in the island arc quartz gabbro-norite-dolerites of the Ayu-Dag intrusion, Rocky Crimea
Spiridonov E.M., Filimonov S.V., Semikolennyh E.S., Korotaeva N.N., Krivitskay N.N.
Abstract

Сhevkinite-(Се) and perrierite-(Се) are minerals characteristic for alkaline magmatic rocks and high-temperature alkaline metasomatites, and yet they are typical accessory minerals in Mesozoic island-arc gabbroids of the Rocky Crimea. Early magmatic mineral associations in these low-alkaline rocks of Ayu-Dag intrusion include accessory Ti—Zr—LREE minerals under-saturated in silica: chevkinite-(Се), perrierite-(Се), zirconolite, baddeleyite. Сhevkinite and perrierite occur as isolated shortly prismatic crystals up to 0.1 mm in size and strongly corroded inclusions in center of late-magmatic allanite-(Ce) crystals. Both minerals are the main concentrators of lanthanides in Aju-Dag gabbroids. Distribution of lanthanides in them is as following: Ce ˃> La > > Nd >> Pr > Gd, Sm, Tb, Dy. Contents of lanthanides in chevkinite and perrierite are identical: Ce (54—58 % REE) — La (25—31 %) — Nd (12—20 %). Contents of Zr, Th, Y, Sc in both polymorphs are identical also. Сhevkinite-(Ce) of isolated crystals is magnesium-dominant; its composition is: [Cе1.5La0.8—0.9Nd0.3—0.4Pr0.1(Gd+Sm+Tb+Dy)0.1Y0.2Sc0.1Ca0.7—0.8Na0.1]4(Mg0.5Fe3+0.5)1 × (Fe3+1.1—1.2Ti0.4—0.7Zr0.1—0.2Al0.1—0.2)2Ti2[(Si3.7—4Al0.3—0)4O22]. Сhevkinite-(Ce) from inclusions in allanite is poor in Mg, its formula is: [Cе1.5—1.7La0.6—0.9Nd0.5—0.6Pr0.1(Gd+Sm)0.1Y0.1—0.2Sc0.1Ca0.6—0.8Na0.1]4 × (Fe2+0.6—1Mg0—0.1Fe3+0—0.4)1(Ti0.8—0.9Fe3+0.3—0.7Al0.2—0.4Zr0—0.2)2Ti2[(Si3.9—4Al0.1—0)4O22]. Perrierite-(Ce) composing idiomorphic crystals is magnesium-dominant, its composition is: [Cе1.2—1.6La0.6—0.8Nd0.3—0.4Pr0.1 × (Gd+Sm+Tb+Dy)0.1Y0.1Sc0.1Ca1.0—1.1Sr0—0.1Na0.1]4(Mg0.9—1Fe3+0.1—0)1(Fe3+1.0—1.2Al0.2—0.7Ti0.3—0.5Zr0—0.2)2Ti2 × [(Si3.9—4Al0.1—0)4(O21.3—21.5OH0.7—0.5)22]. Perrierite-(Ce) occurring inside allanite is poor in Mg, with the formula: [Cе1.3—1.5La0.7—0.8Nd0.3—0.5Pr0.1(Gd+Sm)0.1Y0.1Sc0.1Ca1.1—1.3Na0.1]4(Fe2+0.4—0.5Fe3+0.2—0.4Mg0.2)1 × (Al0.5—0.7Ti0.3—0.8Fe3+0.3—0.9Zr0.1—0.3)2Ti2[(Si3.9—4Al0.1—0)4(O21.4—22OH0.6—0)22]. Presence of chevkinite, perrierite and zirconolite in unusual geochemical settings may be explained perhaps by poor development of late-magmatic processes in near-surface intrusions of Crimeaʼs Mesozoids.

Perhaps, the presence of chevkinite and perrierite, as well as zirconolite in unusual geochemical settings can be explained by poor development of late-magmatic processes in near-surface intrusives of the Mountain Crimea mesozoids.

Zapiski RMO (Proceedings of the Russian Mineralogical Society). 2019;148(4):61-79
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Accessory zoned chromites from Archean komatiites of the Karelian craton: metamorphic fingerprints
Svetov S.A., Chazhengina S.Y., Singh V.K., Rybnikova Z.P., Mishra S.
Abstract

SEM and LA-ICP-MS analyses were used for the study of accessory chromite in Archean (3.0—2.8 Ga) komatiites from the most representative greenstone belts of the Karelian Craton. Zoned chromite, subjected to varying degrees of metamorphic alteration, was identified in the komatiites. Two types of zoned chromite, differing in the composition of their cores, were recognized. Al-rich zoned chromite of type I shows the low extent of metamorphic alteration and has cores with Cr# 0.70—0.86, Mg# 0.03—0.12, and Fe# 0.06—0.23. It is enriched in Zn, Co, and Mn but strongly depleted in Ga, Ni, and V. The study reveals that the primary magmatic distribution of minor and trace elements in the cores was strongly redisturbed during prograde metamorphism of greenschist to low amphibolite facies. Zoned chromite with the low Al2O3 content of type II has cores with higher Fe# (0.42—0.49), Cr# (0.88—1), and lower Mg# (0—0.04) as compared to cores of Al-rich chromite, that corresponds to the more intensive metamorphic alteration. Since the primary composition of studied zoned chromite was significantly obliterated during metamorphism, established patterns can be used as a guide for the reconstruction of metamorphic processes.

Zapiski RMO (Proceedings of the Russian Mineralogical Society). 2019;148(4):80-94
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Organic mineralogy and biomineralogy
Amino acid composition of gallstones and its connection with the mineral component
Mashina E.V., Shanina S.N.
Abstract

The study of the amino acid composition of gallstones of the Komi Republic residents has shown the significant differences in cholesterol and pigment specimens. It has been revealed that during formation of the carbonate or phosphate component in gallstones, the specificity of the protein component is of great importance. It is shown that the content of amino acids is higher in samples with presence of the mineral component and is non-uniform through the cross-section of gallstones. The presence of D-forms of amino acids in pigment and cholesterol gallstones is a consequence of the participation in their formation of various microorganisms.

Zapiski RMO (Proceedings of the Russian Mineralogical Society). 2019;148(4):95-109
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Discussions, critique, bibliography
Nature of diversity of diamonds in kimberlites
Shkodzinskiy V.S., Beskrovanov V.V.
Abstract

The one-way evolution of inclusions in diamonds and its ultra-long duration (more than 2.8 Ga) provide evidence that the crystallization of diamonds took place from the fractionated peridotitic layer in the global magmatic ocean. Diamonds were formed as a result of accumulation of carbon in residual kimberlitic melts. The increment of SiO2 concentration in the melts caused increase in its viscosity, decrease of diffusion velocity and degree of carbon oversaturation. These resulted that the layered diamond crystallization mode was changed by the radial one, diamond octahedrons transformed into rhombic dodecahedrons and cubes, varied sculptures were created on diamond crystals faces.

Zapiski RMO (Proceedings of the Russian Mineralogical Society). 2019;148(4):110-124
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The Cure principle of symmetry in an open system
Rakin V.I.
Abstract

The symmetry Curie principle was formulated within the framework of the "equilibrium" paradigm and bears the imprint of a rigid deterministic causal relationship. However, for an open thermodynamic system in the limit stationary mode and especially subject to a short-term effect of a dissymmetry factor, the Curie principle requires clarification. The original group-theoretical content of the Curie principle implies its discussion within the confines of the physical model for an observed phenomenon.

Zapiski RMO (Proceedings of the Russian Mineralogical Society). 2019;148(4):125-128
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