FT-IR spectroscopic analysis to study the firing processes of prehistoric ceramics

In this work, we present a FT-IR absorbance investigation on prehistoric ceramics with the aim of characterizing the phase transformations that occur during the cooking processes. The measurements were performed on several potteries belonging to the Middle Bronze Age excavated in the Catania hinterland (Sicily, Southern Italy). Based on the macroscopic observation, the samples may be distinguished on coarse and fine ceramics, and the petrographic study showed a strongly heterogeneous structure and composition. The results were compared with the data obtained by means of X-ray diffraction (XRD) and with the microscopic qualitative observations of the birefringence of the groundmass. The whole set of the data showed a firing temperature in the 800-900 °C range. The simultaneous presence in several samples of calcite and clay minerals and of new-formed Ca-silicates should be indicative of a quite primitive technological firing process with strong temperature variation inside the kiln.