Evaluation of Classification Criteria in the 4M Method Applied to Ordinary Chondrites

In 2019, our group introduced a new method for the classification of ordinary chondrites based on Mössbauer spectroscopy results. In 2026, this method was further developed. In the original version, the classification criterion was the level of similarity determined on the basis of the Mahalanobis distance, whereas in the updated version a Bayesian approach based on maximum a posteriori probability was proposed. The aim of the study is to evaluate the effectiveness of the new approach used in the revised 4M method, with particular emphasis on the role of a priori probability in the classification procedure. Three classification variants were compared.