Social hierarchy and the choice of metal recycling at Anyang, the last capital of Bronze Age Shang China

Ruiliang Liu,Qin Cao,Philly Howarth,Victoria Sainsbury,Peter Bray,Limin Huan,A Mark Pollard,Cheng Liu,Jigen Tang,Yuting Fu,Bohao Yao

doi:10.1038/s41598-020-75920-x

Abstract

Anyang, the last capital of the Chinese Shang dynasty, became one of the largest metal consumers in Eurasia during the second millennium BCE. However, it remains unclear how Anyang people managed to sustain such a large supply of metal. By considering the chemical analysis of bronze objects within archaeological contexts, this paper shows that the casting and circulation of metal at Anyang was effectively governed by social hierarchy. Objects belonging to the high elites such as Fuhao, particularly the bronze ritual vessels, were made by carefully controlled alloying practice (primary) using very pure copper, whereas the lower elites only had access to bronzes made by secondary alloying practice and copper with more impurities. Such contrasts allow scholars to identify those objects which are less likely to have been made by mixing and recycling, which has very important implications for the chemical and isotopic determination of provenance for future studies.

Highlights

Metal is one of the earliest fully reusable materials discovered by human beings
Does the recycling of metals, which has been commonly encountered in many parts of Bronze Age Eurasia, occur in China? If so, what social factors could affect recycling in China? In its early dynasties (Shang and Zhou, ca. 1600–221 BCE), large numbers of extraordinary bronze vessels were produced
The broader issue is what strategy was implemented to ensure the sustainable supply needed to maintain metal production in Bronze Age Shang China, the first Chinese dynasty which shows overwhelming archaeological and textual evidence that huge quantities of metal were removed from the contemporary metal circulation and deposited in tombs? So far, the study of recycling in China is limited by the lack of contemporary written records

Summary

Shang China

This could be the result of several processes, such as objects being made from different alloying recipes (implemented by different foundries or requested by various patrons), or mixing and recycling of finished objects/copper ingots, leading to less well controlled and (generally) diluted (lower) alloy compositions. The products from the lower line are for the low-elites, based on secondary alloying practices with relatively low-quality or recycled metals from multiple sources or foundries, making it nearly impossible for the craftspeople to precisely control the variation of tin or lead in the final objects This two-line hierarchical model guarantees the requirements of people from different social classes for metal objects. Practice with high-quality materials enables craftspeople to produce objects with targeted weight, colour, shape and decoration, whereas the needs for metal objects of the low elites can be fulfilled by lower-quality or recycled metals

Conclusions and future directions

Author contributions

Findings

Additional information