Examination of ancient pottery using the scanning electron microscope

A SEQUENCE of pottery sherds from Iraq spanning the period about 6000 BC to 750 AD and two sherds from Turkey about 5000 BC have been examined using a scanning electron microscope (SEM). This examination provided information on the internal morphology developed during firing and in particular information on the extent of vitrification (the glassy phase) and the pore structure1,2. The extent of vitrification provided a useful parameter for characterising the quality of the pottery since it influences several physical properties (such as, hardness, strength, permeability) which are relevant to its suitability for the various uses to which it might be put. In addition by refiring samples of the pottery at known temperatures and determining, by re-examination with the SEM, the temperature at which an increase in the vitrification had occurred, it was possible to estimate the firing temperature used in antiquity.