SYNCHROTRON STUDIES OF BAN CHIANG ANCIENT POTTERY

The pottery shards excavated from the Ban Chiang archaeological site a UNESCO world heritage site, Thailand are well known for their distinctive red paint and exquisite designs. The pottery assemblages are found to span 3 periods: Pre-metal, Bronze, and Iron Ages. The aim of this research is to explore the firing techniques used for pottery production during these time spans. X-ray absorption spectroscopy carried out at Beam line 8 (BL-8) of the National Synchrotron Research Center (NSRC), Thailand was used to measure Fe 2+ and Fe 3+ distributions in the pottery. A range of other analytical techniques, including X-ray Diffraction (XRD), X-ray Fluorescence (XRF), Fourier Transform Infrared Spectroscopy (FT-IR), Differential Thermal Analysis (DTA), and Thermal Gravimetric Analysis (TGA) were also used to obtain the chemical compositions and information on changes in the thermal properties of the samples. The Fe K-edge absorption spectra of mixed standard iron compounds and the red clay ceramics fired under control conditions at various temperatures are used as a reference standard to determine the ferric/ferrous ratio in the pottery shards. Results revealed that all Ban Chiang pottery was likely fired under partial reducing conditions, but the firing temperature used was higher in the Pre-metal Age than those in the Bronze and Iron Ages.