X-ray photoemission spectroscopy and secondary-ion mass spectroscopy applied to the compositional study of pre-colonial pottery from Pantanal, Brazil

X-ray photoemission spectroscopy (XPS) and time-of-flight (TOF) secondaryion mass spectroscopy (SIMS) have been applied to investigate potsherd samples from Pantanal, Brazil. One of the potsherds presented burnt bone as an additive, which was characterized by XPS as carbonate hydroxyapatite. For shell-tempered ceramics the phase present in shells after firing was identified by X-ray diffraction. TOF-SIMS was used to study the distribution of quartz as temper in one of the sherds. XPS was also applied to the characterization of the finishing external layer of the ceramic vessels. In this case, based on the Fe 2p spectra of the sherd's interior and outermost layers, it was possible to prove that their difference in coloration is due to black heart formation. Hierarchical clustering analysis and principal component analysis of the XPS elemental data enabled the potsherds to be classified with respect to their clay composition.