Identification of Ryukyu lacquerwares by pyrolysis-gas chromatography/mass spectrometry and 87Sr/86Sr isotope ratio

• Six kinds of important ancient lacquerwares were analyzed.
• Identification of lacquer species by Py-GC/MS.
• Provenance of lacquer tree was cleared by strontium isotope ratios.
• Revealed lacquer techniques of ancient Ryukyu lacquerwares.

Six pieces of lacquer obtained from Ryukyu lacquerwares produced in the 17–19th century in the Ryukyu Kingdom were analyzed by pyrolysis gas chromatography/mass spectrometry and 87Sr/86Sr isotope ratio measurements to determine the identity of the lacquer source. The results were compared with the standard of natural lacquer film to discriminate lacquer species. Four pieces were made used lacquer sap collected from Toxicodendron vernicifluum lacquer tree, and other two pieces were made with lacquer sap tapped from Toxicodendron succedanea lacquer tree according to the characteristics of the pyrolysis products. All 87Sr/86Sr isotope values of urushiol lacquerwares are over 0.71, suggesting that the origin of lacquer trees were the Asian continent.