Investigation of medieval archeological ceramics using XRD, WD-XRF and SEM/EDX analyses

Some medieval ceramic finds obtained from Zeytinli Island (Erdek, Turkey) excavations were examined using archaeometry techniques. Firstly, the color values of the ceramics were determined using the Munsell color system. The morphological structures, chemical and mineralogical contents of the samples were determined by scanning electron microscopy/energy-dispersive X-ray, wavelength-dispersive X-ray fluorescence (WD-XRF) and X-ray diffraction (XRD) analyses. Information was obtained about the matrix, mineral phases, particle sizes and porosity of ceramics by elemental analyses by observations SEM, XRD and XRF measurements. Quartz, vermiculite, sepiolite, illite, calcite and hematite mineral phases were found in the AD sixth- and seventh-century ceramic samples by evaluating the obtained XRD measurements. Berlinite, caracolite and enstatite phases were observed in AD thirteenth-century ceramics. In the samples, the elements oxygen (O), magnesium (Mg), aluminum (Al), silicon (Si) and calcium (Ca) were found in major amounts. The compounds silicon dioxide (SiO₂) and aluminum oxide (Al₂O₃) were found to have varying concentrations of 67.37–52.95 and 34.39–15.65%, respectively. Elements such as copper (Cu), strontium (Sr), rubidium (Rb), nickel (Ni) and manganese (Mn) were observed in trace amounts. The element lead (Pb) was found in the glazes of the studied ceramics excavated from the Eastern Church. It was seen that the chemical compositions and production techniques of Byzantine and late Roman ceramics were nearly similar.