Material characterization of solders used in bronze vessels from the Lu state (c. 560–370 BCE) reveals the diachronic change of soldering techniques

Surprising combinations of bronze vessels with multiple cultural elements have been unearthed in Shu tombs in southwestern China, indicating a significant connection with the middle and lower reaches of the Yangtze River. However, there is currently no comprehensive evidence for the provenance of these foreign style vessels, and little emphasis has been given to the diachronic changes in the interaction between Shu culture and its surroundings. This article investigates the bronze vessels unearthed from the Shuangyuan Village Cemetery in Chengdu during the Eastern Zhou Dynasty and aims to deeply reveal the production and exchange of bronze vessels unearthed from Shuangyuan Village Cemetery from the perspective of lead sources through typological analysis and scientific analysis. The study clarified the ages of the local style Shu culture vessels and foreign style vessels, and the latter exhibited a strong influence of the Chu and Yue cultures. Lead isotope analysis shows that the lead source characteristics of foreign style vessels are consistent with those of vessels from Chu‐Yue culture at the same time, and they may be imported from Chu directly. The specific interaction modes of Shu and Chu underwent a clear transformation during the middle Warring States period.

Abstract

Diachronic change in the Shang dynasty ritual package

While oxidation products of unsaturated fatty acids, for example dicarboxylic acids (hereafter diacids), must form during the use of unglazed ceramic vessels for the processing of animal and plant products, such components have never been observed during studies of absorbed lipids. Their absence from the extractable lipid fraction is presumed to be the result of their loss from potsherds through groundwater leaching. Lipid oxidation products including short-chain dicarboxylic acids, ω-hydroxy acids and longer-chain hydroxy and dihydroxy acids have now been observed as components probably covalently bound into solvent insoluble residues of potsherds recovered from waterlogged deposits. These components were only revealed following alkaline treatment of the insoluble residues. A similar mixture of diacids was observed in high abundance in the free lipid fraction of vessels recovered from an exceptionally arid deposit where groundwater leaching would never have occurred. These results confirm the formation of oxidation and probable polymerization products of unsaturated fatty acids during vessel use and burial.

Material characterization uncovers sophisticated mould-making techniques of the middle-Shang period (14th-13th BCE)