The First Occurrence of Qandilite in Russia

R. A. Oktyabrsky, S. A. Shcheka, A. M. Lennikov and T. B. Afanasyeva
Far Eastern Geological Institute, Academy of Sciences, Vladivostok 690022, Russia

Abstract: Numerous small octahedra of a black, brittle, magnetic mineral were found in calciphyre and brucite marble, occurring in the northern part of the exocontact zone of the Kondyor ultramafic-alkalic massif (south-eastern part of the Aldan Shield, 250 km north west of sea port Ayan). Their composition corresponds to the group from titanium magnesioferrite (11.53% TiO2) to titanium-rich magnesian spinel (27.34% TiO2), similar to spinellide found in Greenland (Gittins et al., 1982) and in Iraq (Al- Hermezi, 1985) and approved by the Commission on New Minerals as a new mineral named qandilite. Hardness, specific gravity, and reflectance of Kondyor qandilite are similar to those of the Iraq mineral. Peaks of IR-absorption spectra are equal to 580–590cm-1 (ν1) and 431–438cm−1 (ν2). There is a positive correlation between lattice parameters and the amount of Mg2TiO4: from 8.368 Å at 26.6% to 8.429 Å at 60.4%. Kondyor qandilite crystallized together with geikielite, oxidized alumina spinel (8.55% Fe2O3, ftotal= 16.5%), periclase, and forsterite.

Keywords: qandilite • Ti-spinellide • Kondyor • Russia

Mineralogical Magazine; September 1992 v. 56; no. 384; p. 385-389; DOI: 10.1180/minmag.1992.056.384.11
© 1992, The Mineralogical Society
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