Ancient glassware travelled the Silk Road: Nondestructive X-ray fluorescence analysis of tiny glass fragments believed to be sampled from glassware excavated from Niizawa Senzuka Tumulus No. 126, Japan

X-ray fluorescence analytical techniques were applied to two pieces of glass fragments because they are believed to be sampled from two pieces of important glassware, a facet-cut bowl and a deeply-blue colored dish, excavated from Niizawa Senzuka Tumulus No. 126, Nara, Japan (late 5th century). Two different provenances were estimated as primary production area for the two glass fragments. One fragment has a chemical composition being a good match with that of Sasanian glass excavated at Veh Ardasir in central Iraq. Conversely, composition of another fragment is consistent with common blue-green colored Roman glass manufactured during the imperial period. If these glass fragments are actually identical to the ancient glassware excavated from Nara, our results can provide scientific evidence how various cultures were introduced to and accepted by ancient Japan. Concomitantly, they are also evidence of an extremely widespread Silk Road trading from the Mediterranean and West Asia to the Far East of Japan during the 1st millennium AD.