Pottery production and exchange at the Guandu site, Taiwan: A petrographic and mineralogical study

The Guandu site is one of the earliest identified archaeological sites in northern Taiwan and is situated at a geographically and archaeologically strategic position within a region rich in well-studied prehistoric sites. Early surveys and excavations suggest multiple cultural layers spanning from the Neolithic to the Iron Age; however, materials recovered during the 1943 excavation have remained largely unstudied since their deposition in museum archives. In this paper, we focus on pottery technology, provenance, and exchange from the Late Neolithic to the Iron Age, based on ceramic assemblages from the 1943 Guandu excavation. A total of 154 pottery samples were analyzed using thin-section petrography, of which 18 were additionally analyzed by synchrotron X-ray diffraction (XRD) to investigate paste recipes, clay preparation practices, and firing strategies. Results indicate four distinct fabrics, alongside seven less-represented fabrics and three loners, suggesting the exploitation of diverse raw material sources. These patterns may reveal technological variability, diachronic shifts in production practices, and potential evidence for interaction and exchange among multiple social groups at Guandu and across Taiwan.