Small, disc-shaped shell beads are recorded as mortuary offerings in many Neolithic and Bronze Age burials in Southeast Asia. Yet the provenance of these artefacts is often obscure, as production processes involve the removal of diagnostic morphological features, negating taxonomic classification. Here, the authors report on the combined isotopic and morphological analysis of a subset of shell beads from the site of Ban Non Wat in north-east Thailand. In addition to identifying freshwater sources for nearly all the beads, the results suggest the presence of multiple shell production centres—each with access to distinct aqueous environments—and widespread exchange in the Bronze Age.

Indian Ocean maritime networks have become a special focus of research in recent years, with emphasis not only on the economics of trade but also the movement of domesticated plants and animals (see Fuller et al. in Antiquity 2011: 544–58). But did such contacts inevitably lead to radical social change? Excavations at Tumbe reveal a settlement of the late first millennium AD that was heavily engaged in the traffic in exotic materials and may have been producing shell beads for export. This activity seems to have flourished within a domestic context in a village setting, however, and does not seem to have stimulated pronounced social stratification nor to have led inexorably towards urbanisation. These results demonstrate that some communities were able to establish a stable balance between the demands of the domestic economy and long-distance trade that could persist for several centuries. Activities at Tumbe should hence be viewed in their own right, not as precursors to the formation of the Swahili trading towns of the later medieval period.