Study on ancient glass and faience using SR spectroscopy

There are about 40 specimens of ancient glasses and faience that were mainly excavated in Egypt and Iran. Their age was between about the 15th century BC and about the 4th century AD, many of which were around the 2nd century AD (Roman Empire era). Ancient glass is made of silica, calcium, and alkaline salts. The faience has a two-layer structure consisting of vitreous surface (glaze) and siliceous core. Analysis was performed with non-destructive fluorescent X-rays using the large radiation SPring 8. A large amount of antimony was detected as a clouding agent from lid-equipped glass containers with the King's inscription of the Egyptian dynasty around the 14th century B.C. The glass compositions around the Roman period were relatively homogeneous in element compositions, and the regional features were not clear. The glasses of Egypt Dynasty and Roman period had different ratios of rare earth elements. In the core of faience, this study was able to confirm a difference in regional element compositions, but there was no obvious regional difference in the glaze on the surface. Vanadium, gallium, selenium, etc. were detected from the yellow part of faience. In the future, this will become a clue for the production place of the yellow glaze or the identification of raw materials. (A.O.)