The interior and the fusion crust in Sariçiçek howardite: Study using X-ray diffraction, magnetization measurements and Mössbauer spectroscopy

The meteorite Sariçiçek, a 2015 howardite fall in Turkey, was analyzed using various physical techniques. Both the interior and the fusion crust were studied by optical and scanning electron microscopy with energy dispersive spectroscopy, X-ray diffraction, magnetization measurements and Mössbauer spectroscopy. The main and minor iron-bearing phases such as orthopyroxene, Ca-poor and Ca-rich clinopyroxene, chromite with hercynite, Fe2+ and Fe3+ ilmenite, troilite, ?-Fe(Ni, Co), ?2-Fe(Ni, Co) and ?-Fe(Ni, Co) phases were identified. The ratios of Fe2+ occupancies in the M1 and M2 sites in the silicate phases as well as the equilibrium Fe2+ and Mg2+ cations distribution temperatures (Teq) for orthopyroxene were estimated using X-ray diffraction and Mössbauer spectroscopy, which appeared to be in a good agreement: for example, Teq were 886 and 878 K, respectively. The glass-like fusion crust of Sariçiçek consists of orthopyroxene with ferrous and ferric compounds that are likely products of combustion and melting. © 2019 Elsevier B.V.Ministry of Education and Science of the Russian Federation, Minobrnauka Government Council on Grants, Russian Federation: ? 02. Ural Federal University, UrFU Ministry of Science and Higher Education of the Russian Federation: 3.1959.2017/4.6The authors wish to thank Dr. E.I. Denisov (Institute of Physics and Technology, Ural Federal University) for his kind help with chemical analysis using X-ray fluorescence spectroscopy. This work was supported by the Ministry of Science and Higher Education of the Russian Federation (the Project ? 3.1959.2017/4.6 ) and Act 211 of the Government of the Russian Federation , contract ? 02.A03.21.0006 .The authors wish to thank Dr. E.I. Denisov (Institute of Physics and Technology, Ural Federal University) for his kind help with chemical analysis using X-ray fluorescence spectroscopy. This work was supported by the Ministry of Science and Higher Education of the Russian Federation (the Project ? 3.1959.2017/4.6) and Act 211 of the Government of the Russian Federation, contract ? 02.A03.21.0006