Classification methods of ordinary chondrites – what can they tell us about meteorites?
M. Jakubowska, A. Grabias, M. Woźniak, J. Gałązka-Friedman & K. Szopa
Interactions, Volume 247, article number 36, Conference Proceeding, Published: 18 February 2026
“Ordinary chondrites are the most common meteorites falling to Earth, which contain iron distributed among four major mineral phases: olivine, pyroxene, metallic Fe–Ni and troilite. Their classical classification is based on determining the fayalite (Fa) and ferrosilite (Fs) contents in silicates using an electron microprobe. The Warsaw group developed new classification method approach that relies on Mössbauer spectroscopy combined with multidimensional discriminant analysis and a reference database of meteorites with known petrographic types – the 4M method. In this study, we compare the classical Fa–Fs classification with the 4M method for a dataset of 33 equilibrated ordinary chondrites (H, L, LL) for which both microprobe and Mössbauer measurements are available. The Mössbauer spectra were decomposed into subspectra corresponding to olivine, pyroxene, metallic Fe-Ni and troilite, allowing the relative distribution of iron among these phases to be quantified. The results show a clear correlation between the fayalite content and the spectral area of olivine, which is consistent with mineral condensation sequences predicted for the primordial solar nebula. In contrast, no correlation is observed between the ferrosilite content and the Mössbauer-derived pyroxene abundance.”
