Elemental analysis of glass ornaments from Liziwei: uncovering local exchange networks in southwestern Taiwan

Abstract This study presents a comprehensive analysis of glass ornaments excavated from the Liziwei site in southwestern Taiwan (the 1 st to the 8 th century CE) to explore the dynamics of local and trans-regional exchange network during the Metal Age. Using Laser Ablation - Inductively Coupled Plasma - Mass Spectrometry (LA-ICP-MS) and Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM-EDS), we identified three principal chemical groups: mineral soda high alumina glass, soda plant ash glass and potash glass. The chemical compositions of these glass groups demonstrate Liziwei's integration into a broad maritime exchange network that connected Taiwan with Southeast Asia, South Asia and West Asia. However, our findings also reveal the existence of a localised exchange network within southwestern Taiwan, characterised by distinct regional preferences in glass ornament styles and chemical compositions. Comparison with Daoye, Daoye South and Wujiancuo reveals continuity in glass chemical groups and cultural practices, suggesting sustained regional interactions distinct from those in other parts of Taiwan. The findings indicate that glass exchange likely intensified during the Middle Metal Age, coinciding with increased settlement activity and higher concentrations of glass beads in burials. These results highlight the interplay between long-distance exchange and localised circulation, providing new insights into the evolution of exchange activities in prehistoric Taiwan.