Study on glaze tiles from the Central Capital of the Jin dynasty in North China

Glazed tiles constitute a hallmark of high-ranking ancient Chinese architecture. However, systematic scientific research on imperial glazed tiles from the Jin dynasty remains scarce. This study investigates nine imperial glazed tile fragments excavated from the Central Capital of the Jin dynasty (1115–1234 CE). Compositional and mineralogical data imply the bodies originated from the Longquanwu kiln in Beijing. The engobe is composed of high-Al clays, differing from calcareous engobes at other Jin and Yuan capital sites. The glazes belong to a typical PbO-SiO₂-Al₂O₃ system and were applied using a single-firing technique. Furthermore, lead isotope analysis identifies the Liaodong region as the primary lead source for the glazes. Notably, one tile exhibits highly radiogenic lead isotopes with extremely high ²⁰⁸Pb/²⁰⁴Pb ratios, distinct from any published data on Chinese lead ores or cultural heritage artifacts.