Prehistoric Stone Ornaments from Phromtin Tai, Central Thailand: New Perspectives on Workshop Traditions through the Study of Drilling Methods

The multi-component site of Phromtin Tai, Thailand is notable for its long occupation from the Late Bronze Age (ca. 700 - 500 B.C.E.) through early historic periods (ca. C.E. 500 - 900). Multiple field seasons of excavation in burial and habitation areas at the site have recovered a large number of glass and stone beads. Here we present the study of 57 stone beads from the site using qualitative and quantitative methods that demonstrate the presence of multiple stone ornament workshop traditions. Examination of perforations from beads and pendants made from regionally available raw materials of marble, nephrite, serpentine, and other undetermined stone have identified the use of metal drills with abrasives and diamond drills. These drilling techniques along with the distinctive shapes of some finely made beads, as well as the reworking of older broken beads suggests the presence of different scales and organization of local production in Southeast Asia. The different shapes and production processes of carnelian and banded agate beads also may represent various workshop traditions. Some of these latter beads may have originated in South Asia, while others may have been made in different regions of Southeast Asia. This study demonstrates that careful examination of ornament production techniques, and especially bead perforation technology, can be used to identify the presence of different workshop traditions allowing for more fine-grained consideration of inter- and intra-regional bead exchange networks in Southeast Asia. The presence of many semi-precious stone beads of different materials and having morphologically and technologically distinct features at Phromtin Tai demonstrate the active consumption of the beads by social elites at the site. These diversified and exotic status markers represent an intensification and acceleration of the economy and social complexity at Phromtin Tai. KEYWORDS: stone beads, bead drilling, bead production, Central Thailand, Iron Age.