Figure 38

SEM images of gas vesicles in melted material from the palace. (a), (b) Vesicles in melted pottery are lined with crystals of iron and iron oxide (elemental Fe, Fe2O3, and/or Fe3O4). (c)–(g) Vesicles in melted mudbrick and roofing clay often are lined with a variety of crystals including elemental Fe, iron oxide, Fe phosphide (Fe2P), manganese oxide (MnO), calcium phosphate (Ca3(PO4)2), and calcium silicate (CaSiO3). These crystals are consistent with vapor deposition at high temperatures.