Hostname: page-component-586b7cd67f-t7czq Total loading time: 0 Render date: 2024-11-28T16:21:54.975Z Has data issue: false hasContentIssue false

The first occurrence of qandilite in Russia

Published online by Cambridge University Press:  05 July 2018

R. A. Oktyabrsky
Affiliation:
Far Eastern Geological Institute, Academy of Sciences, Vladivostok 690022, Russia
S. A. Shcheka
Affiliation:
Far Eastern Geological Institute, Academy of Sciences, Vladivostok 690022, Russia
A. M. Lennikov
Affiliation:
Far Eastern Geological Institute, Academy of Sciences, Vladivostok 690022, Russia
T. B. Afanasyeva
Affiliation:
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 580-590 cm−1 (v2) and 431-438 cm−1 (v2). 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.

Type
Mineralogy
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1992

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Al-Hermezi, H.M. (1985) Qandilite, a new spinel end-member, Mg2TiO4, from the Qala-Dizeh region, NE Iraq. Mineral. Mag., 49, 739–44.CrossRefGoogle Scholar
Andreev, D.V. (1987) Kondyor massif of ultramafic and alkaline rocks. Nauka, Novosibirsk, 76 pp. (in Russian).Google Scholar
Gittins, J., Fawcett, J.J., and Rucklidge, J.C. (1982) An occurrence of the spinel end-member Mg2TiO4 and related spinel solid solutions. Mineral. Mag., 45, 135-7.CrossRefGoogle Scholar
Khudolozhkin, V.O., Narnov, G.A., and Karabtsov, A.A. (1986) Infrared spectra of spinellide solid solutions by (Mg,Fe2+)(Fe3+,AI,Cr)204 system. Mineral Zhurn., 8, 1724.(in Russian).Google Scholar
Shcheka, S.A. (1981) Igneous rocks of DSDP Leg 61, Nauru Basin. Init. Repts DSDP. US Govt. Print. Office, Washington, 61, 633-71.Google Scholar
Urusov, V.V. and Karabtsov, A.A. (1983) On stability of chromite-magnetite spinels. Mineral. Zhurn., 5, 316.(in Russian).Google Scholar
Waldron, R.D. (1955) Infrared spectra of ferrites. Phys. Rev., 99, 1727–35.CrossRefGoogle Scholar