Alloy ratio and raw material sourcing of Warring States Period bronze bracelets in Huili County, Southwest China by pXRF and MC-ICP-MS

Up to now, there have been few monographic analyses of metal ornaments in China. This study presents a case study of the metallurgical archaeology on bracelets from Huili (会理), which may shed light on the issue as production status, technical level, use of raw material and workmanship exchange. Ten bronze bracelets from the Fenjiwan (粪箕湾) site, Huili County and nine ancient slags within 2 km were analyzed by pXRF and MC-ICP-MS methods. The classification of bronze bracelets according to alloy ratio is exactly the same as that of lead isotope. One group used local copper from Huili without adding lead, while the other group added lead material from the middle reaches of the Yangtze River. Combined with other relevant data, the results indicate that the technology route of bronze in Southwest China was from Cu-Sn binary alloys to Cu-Sn–Pb ternary alloys, and during the Warring States period (475-221 BC), this region may have certain contacts and exchanges with the middle reaches of the Yangtze River and even the Central Plains.