Metallurgical strategies at Sanxingdui: bronze production and resource reuse in Late Shang, China

Abstract This study investigates the metallurgical traditions and resource circulation of the Sanxingdui culture through alloy compositional and lead isotope ratio analyses of 79 bronze samples from Sanxingdui Pits 1 and 2. The results reveal a predominance of lead-tin bronze characterised by ubiquitous high lead content, while tin levels were more strictly managed, particularly in bronze vessels. All samples exhibit the highly radiogenic lead (HRL) signature characteristic of the Shang period. The persistence of HRL at Sanxingdui after its decline in the Central Plains is consistent with a shift from external procurement towards the internal circulation and reuse of metal. We advance the remelting of earlier HRL bronzes as a working hypothesis to account for this pattern. These findings illuminate how regional polities adapted their metallurgical strategies to shifting geopolitical landscapes.