Regional Variations in Bronze Tinning Techniques in Late Bronze Age China: Experiments, Analyses, and Implications

ABSTRACT The tinning technique holds a special place in the developmental history of surface treatment techniques for Chinese bronzes. To gain a deeper understanding of the diverse technical characteristics and technological exchanges of early Chinese tinned bronzes, four tinning techniques—foil wrapping, rubbing, dipping, and pouring—were reconstructed through experimental archaeology. Microstructural and compositional analyses using microscopy, scanning electron microscopy (SEM), and energy‐dispersive spectroscopy (EDS) were conducted to examine coating thickness, surface morphology, microstructure, and compositional profiles under different processing conditions. Comparative analysis with 96 tinned bronzes (90 published and 6 from this article) excavated in three key regions (the Dian culture area, Northwest China, and the Ba‐Shu region) revealed distinct technological divergences: the Dian culture area primarily utilized thin‐layer tinning, characterized by low‐temperature processing and a preference for mechanical polishing to enhance coating properties. In contrast, Northwest China and the Ba‐Shu region employed thick‐layer tinning, demonstrating mature high‐temperature annealing techniques. Spatiotemporal analysis suggests a trend of the tinning technique spreading from the northwest to the southwest along the “Crescent‐Shaped Cultural‐Communication Belt.” These regional variations and transmission patterns underscore the complexity of inter‐ and intra‐regional technological exchange and the localized adaptations among diverse cultural and ethnic groups that occurred during the dissemination of early metalworking technology.