Differential metal supply networks between central and northeast Thailand, and Northwest Cambodia during the Mid-Late Iron Age: silver, copper and lead alloy artefacts from 2nd-8th c. AD Non Ban Jak

Abstract

Sustained archaeometallurgical research since 2008 has permitted the Southeast Asian Lead Isotope Project (SEALIP) to establish the general anthropological and geochemical parameters of late prehistoric and early historic regional nonferrous base metal exchange networks. A 79 artefact assemblage from the mid-late Iron Age (2^nd-8^th c. AD) settlement and residential burial site of Non Ban Jak (NBJ) in lower northeast Thailand gave an opportunity to generate a fine-grained interpretation of copper-base metal supply and demand at the cusp of mainland state formation. Previous hints that the central Thai copper production centres in the Khao Wong Prachan Valley (KWPV) were only weakly active during the Iron Age, were reinforced by the near total absence of the KWPV signature at NBJ, only 165 km to the east. Since 2011, copper production at the Vilabouly Complex (VC) in central Laos has dominated regional consumption signatures, and a simple reading of the NBJ dataset would support this thesis. However, a high-density sampling shows that VC production is not actually consistent with much of NBJ consumption, and thus we must search for other Southeast Asian copper production loci. Finally, being able to analyse multiple artefacts of a range of typologies enables us to identify material culture associations between individuals at NBJ, those at other lower northeast Thai sites, and even between individuals at contemporary sites in northwest Cambodia. Intriguingly, these potential consistencies between individuals at an international scale all concern middle-aged men, possibly reinforcing regional bioarchaeological interpretations of matrilocality.