Figure 41

SEM images of Fe–S–Ca–P-rich grains in mudbrick meltglass from the palace. (a) Melted Fe-rich grain is chemically complex, containing Fe, S, Ca, and P. (b) Manually constructed EDS-based phase map marking areas of Fe oxides (purple, labeled as FeO), FeS (blue), and Ca3P2, calcium phosphide (green). (c) High-temperature melted Fe-rich grain; (d) manually constructed EDS-based phase map showing the area that is predominantly Fe oxide, bordered by a thin rim of FeS.