Southern Sumatra late prehistoric and early historical maritime exchange: First elemental analysis data from glass beads

Sumatra has long been recognized as a pivotal crossroads for trade in the Indian Ocean, with evidence of this activity dating back to the late first millennium when the Srivijaya regional polity emerged. The predominant hypothesis regarding this trade is that upland areas supplied forest products to lowland centers, which functioned as international trading marketplaces. These marketplaces received imported materials, some of which were exchanged with upland groups. However, evidence of this trade is still poorly supported by archaeological materials. This paper presents the first comprehensive study of glass beads from Sumatra via laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) to determine the elemental compositions of the beads. The study encompasses a wide range of sites from upland and lowland areas and various temporal periods, extending from prehistoric to early historic times in Southern Sumatra, Jambi, and South Sumatra Province. The study provides not only improved chronologies, but also data on upland–lowland exchanges that definitively show the upland megalithic sites are not prehistoric, but rather contemporary with Srivijaya. Furthermore, it provides data on the pre-Srivijayan port-settlements and the regional networks in which they were involved, thanks to the presence of certain types of glass, including Mediterranean glass.