GROWTH MEDIUM COMPOSITION OF COATED DIAMONDS FROM THE SYTYKANSKAYA KIMBERLITE PIPE ( Yakutia )
S.Yu. Skuzovatova,b, D.A. Zedgenizova, A.L. Ragozina, and V.S. Shatskya,b
aV.S. Sobolev Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences, pr. Akademika Koptyuga 3, Novosibirsk, 630090, Russia bNovosibirsk State University, ul. Pirogova 2, Novosibirsk, 630090, Russia
Keywords: Diamond, microinclusions, crystallization medium, cathodoluminescence, nitrogen, carbon isotope composition
Pages: 1197-1208 Subsection: PETROLOGY, GEOCHEMISTRY, AND MINERALOGY
Abstract
We present the first results of studying the major- and trace-element composition of microinclusions in the coats of variety IV diamonds from the Sytykanskaya pipe. These microinclusions are of silicate-carbonate composition. Similar compositions are reported for the microinclusions in diamonds from the placers of the northeastern Siberian craton and cuboids from the Internatsional'naya pipe. The microinclusions studied are close to kimberlites and carbonatites in trace-element composition but depleted in HFSE, Mg, and transition metals and enriched in K and LILE. The distribution of incompatible elements in the microinclusions studied is similar to the "table" pattern, which was observed for high-density hydrous-silicic fluids.
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