Extended Data Fig. 4: Iron valence distribution of the analyzed zone No. 2 from the CE5 agglutinate glass.

HAADF-STEM image (a), EELS Fe valent map (b), Fe3+/Fe ratios map (c), and the frequency and cumulative distributions (d) of the Fe³⁺/∑Fe ratios of a randomly chosen zone in the CE5 agglutinate.