Spinels in Meteorites: Observation Using Mössbauer Spectroscopy

Abstract

In this mini-review, we consider the results of various meteorite studies using Mössbauer spectroscopy with a high velocity resolution in order to reveal the minor spectral components related to spinels such as chromite, hercynite, magnesiochromite, magnesioferrite and daubréelite in bulk meteorite matter or in some extracted phases. Spinels observation in the Mössbauer spectra is supported by characterization of the studied samples by means of optical and scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction and magnetization measurements. Mössbauer parameters obtained for extraterrestrial spinels are compared with those obtained for terrestrial analogs published in the literature.

Applications of Mössbauer Spectroscopy in Meteoritical and Planetary Science, Part I: Undifferentiated Meteorites

“…Spectral components assigned to chromite and hercynite have the following ranges of Mössbauer parameters: (i) chromite (δ = 0.598-1.361 mm/s) and (ii) hercynite (δ = 0.843-1.137 mm/s, ∆E Q = 1.149-1.645 mm/s). These ranges of the hyperfine parameters can be related to some deviations from stoichiometry and accessory atoms in these spinels (see [16] and references therein). A spectral component associated with ilmenite was found in the Mössbauer spectrum of Bursa L6 only with the following parameters: δ = 0.949 mm/s, ∆E Q = 0.654 mm/s, A = 0.5%.…”

“…Now, we have about 60 years of experience in the applications of Mössbauer spectroscopy in the study of extraterrestrial materials (the first short reviews see in [9][10][11]). Then, some other reviews were published, for example, (i) concerning ideas of the solar system evolution analysis using Mössbauer spectroscopy data [12]; (ii) study of meteorites [13] and meteoritic Fe-Ni alloy [14,15]; (iii) studies of spinels in meteorites [16]; and (iv) Mössbauer spectroscopy of ordinary chondrites [17]. Further development of Mössbauer spectrometers led to appearance of new possibilities in its applications.…”

Advances in Analysis of the Fe-Ni-Co Alloy and Iron-Bearing Minerals in Meteorites by Mössbauer Spectroscopy with a High Velocity Resolution

“…It should be noted that ilmenite was found in one fragment of Chelyabinsk LL5 (No 2a) only, while in the other four fragments ilmenite was absent. Based on SEM with EDS, XRD and magnetization results confirming the presence of chromite and hercynite in the studied meteorites, the minor spectral components (broad single peak and quadrupole doublet) revealed in the Mössbauer spectra of ordinary chondrites Annama H5 (Figure 16c), Bursa L6 (Figure 16d), Kemer L4 (Figure 17d), Ozerki L6 (Figure 18a), Bjurböle L/LL4 (Figure 18b) as well as NWA 6286 LL6, NWA 7857 LL6 and Chelyabinsk LL5 fragments (Figure 32) were assigned to chromite and hercynite, respectively (some details can be also found in [61] and references therein). Components associated with chromite (broad single peak) and hercynite (quadrupole doublet) were also revealed in the Mössbauer spectrum of Sariçiçek howardite (Figure 21c).…”

Alternative Reductants for Foam Control During Vitrification of High-Iron High Level Waste (Hlw) Feeds

“…Doublets with a centre shift, CS (mm s − 1 ), greater than 0.90, and quadrupole splitting, QS (mm s − 1 ), greater than 2.0 were attributed to Fe 2+ phases [54]. Fitted parameters of the magnetic phases were compared to literature for identification [55][56][57][58]. The results of the Lorentzian fits of the spectra are tabulated in Appendix C.…”