Morphological and mineralogical evolution of microfossils during the heating process: a contribution to the archaeometric study of ceramics

The role of microfossils for the ceramic paste characterization has been revealed through firing experiment. Ceramic samples were prepared with the clay of Monte San Giorgio (Sicily, Italy), that contains many microfossils that suffered relevant changes in the microstructure and chemical composition during firing temperature. The samples were fired at different conditions according to the presumed ancient techniques. The alteration and/or decomposition of mineral phases with temperature was observed with optical and electron microscopy by monitoring the mineral modifications at different firing conditions. In order to validate our approach on archaeological material, the analyses were performed also on ceramic fragments, furnished by the Ceramics Regional Museum ‘‘Antonino Ragona’’ of Caltagirone. The micropaleontological study, as component of the archaeometric analyses, seems to be a useful archaeothermometry for the evaluation of firing processes and sometimes decisive to distinguish the characteristics of the clay used in a given production.