Mineralogical Journal

3-10

Authors: V.M. Kvasnytsya

The crystal morphology, photoluminescence behavior, nitrogen impurity concentrations and Raman spectra of diamonds from Quaternary alluvial deposits of the Eastern Azov region were studied. Macrodiamond from the Mius-Krynka river basin shown ideal rhombic dodecahedron habitus, and their geometric parameters are similar to those of rounded diamonds found in kimberlites and lamproites. The mantle temperature regime for the formation of Azovian diamonds was determined using infrared spectroscopy, the content and state of nitrogen impurities, and other defects in the crystals. Diamonds can be divided into different spectral types namely IaA, IaAB and IIa. They have low nitrogen contents from 19 to 491 ppm, with an average nitrogen content of 148 ppm and they have a relatively high degree of nitrogen aggregation (average value of % B = 33). Thermometric data for the Eastern Azov diamonds are in the range of 1097-1175 ºC for 2 billion years and 1120-1165 ºС for 3 billion years of crystals to stay in the mantle. N3, S1 and 575 nm centers are revealed in the photoluminescence spectroscopic measurements. The Raman shift for diamonds is in the range of 1331.0-1332.1 cm–1. The diamonds are probably associated with mantle eclogites, and they have been brought to Earth’s surface by kimberlites.

20-47

Authors: O.V. Dubyna,S.G. Kryvdik, I.A.Shvaika, I.D. Shvaika, P.F. Yakubenko, L.I. Proskurka

The geochemical features of most distributed rocks from the Korsun'-Novomyrhorod Pluton are considered. The obtained data give reason to assume that the association of basic and intermediate rocks of the pluton was formed because of the differentiation of the primary melt, similar in composition to high alumina tholeiites. It can be inferred that anorthosites were the earliest rocks that appeared in the early stages of plagioclase crystallization. The chondrite-normalized patterns of REE from anorthosites are characterized by the classical distribution of REE for such rocks, with significant positive Eu-anomalies at low REE concentrations. Further evolution of the residual melts enriched by mafic components could lead to the formation of gabbro-anorthosites. Less distributed gabbronorites and norites were formed because of crystallization of residual melts after segregation of anorthositic and gabbro-anorthositic cumulates. Considering the high iron content in all types of rocks, the basic rocks crystallized from residual melts that were genetically related to anorthosites. But ore-bearing norites (Nosachiv-type), in contrast to most distributed basic rocks, had been formed in the early stages because of simultaneous accumulation of feldspar and ilmenite, followed by gravitational precipitation at lower levels of magmatic chambers. The genesis of monzonite-syenite rocks is more enigmatic. Their geochemical features very resemble those in gabbroic rocks, which gives reason to consider them as a result of residual melts crystallization after escaping from anorthositic and gabbronoritic bodies. Subsequent migration and protracted differentiation of such K-enriched melts could cause the appearance of the high-Fe syenites of the Velyka Vyska-type, enriched in REE, Y, Zr, partially Nb, and depleted in Sr and Ba. Although the geochemical characteristics of rapakivi show significant similarities to monzonitic rocks, their genesis remains problematic. It's worth noting that our findings are more consistent with continental crust melting caused by ascending intrusions of basic composition.

60-68

Authors: B.G. Shabalin, K.K. Yaroshenko, O.M. Lavrynenko, N.B. Mitsiuk

The mineral composition and sorption properties of precipitates formed during ozonation of a model solution simulating nuclear power plant wastewater (total mineralization 7 g/dm3, pH = 11.5, T = 60°C, t = 2 hours) 137Cs were studied. The precipitate is represented by finely dispersed spherical particles of metal oxides ranging in size from 20 to 30 nm, forming microaggregates and their associates of various shapes. The composition of the precipitates, along with X-ray amorphous phases, includes Fe(II)-Fe(III) layered double hydroxides (Green Rust), as well as LDH of mixed composition, in particular Fe-Co, and iron oxyhydroxides — goethite and lepidocrocite. The precipitates also contain manganese-containing phases represented by manganese (IV) hydroxide and manganese (II) carbonate with an admixture of manganese oxides, such as Mn2O3∙H2O, MnO, Mn3O4 (gaussmanite). In the process of ozonation, organic compounds that are part of the solutions undergo destruction, co-precipitation with other components of the solution, which is accompanied by the sorption of 137Cs radionuclides on the surface of mineral particles. An increase in the concentration of Fe2+ and Mn2+ cations by 10 times (up to 50 and 100 mg/dm3, respectively) in wastewater reduces the concentration of 137Cs in the initial solution by 50.5%.