Figure 4
From: Shedding New Light on Ancient Glass Beads by Synchrotron, SEM-EDS, and Raman Spectroscopy Techniques
Glass samples divided into two groups according to average Mn oxidation state: (a) Group I: GLL5-4, green, exhibits manganese in the form between Mn2+ and Mn3+; and Group II: samples other than those in group I had the same energy pattern as XANES and showed the pattern peaks that were between MnO and Mn3O4 (all peaks are shown in Supplementary Information); (b) A summary of the average Mn oxidation states and the K-edge energy obtained from the experiments, corresponding to the marks in (a). The line is a linear fit from the reference compounds.
