Exotic blue pigments in the polychrome interior of Yongle Taoist Temple: A case of international trade during the Yuan and Qing Dynasties

Previous studies have established the use of various blue pigments, including both local and imported varieties, in the decoration of architecture in ancient China. However, the application of these pigments in local religious architecture has been understudied. In this study, the chemical analysis of ultramarine blue pigments was conducted on a mural painting retrieved from Yongle Taoist Temple in ancient China. The results showed that both imported and local pigments were used individually in the initial drawing period of the Yuan Dynasty (AD 1271–1368), whereas they were mixed in a later restoration in the Qing Dynasty (AD 1636–1912). Of particular significance, the analysis revealed the presence of lapis lazuli in a local religious relic of the Yuan Dynasty for the first time. Further analysis of the elemental proportions and associated minerals led to speculation about the origin of the lapis lazuli, which is believed to have come from Badakhshan, the northeastern region of Afghanistan, and been transported to Central China through the Silk Road. This finding shed light on the trade routes and usage of these pigments in the construction of religious architecture from the Yuan to the Qing dynasties.