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Ref ID: 28186
Ref Type: Journal Article
Authors: Lertcharnrit, Thanik
Carter, Alison
Title: Recent research on iron age glass and stone beads from Promtin Tai, Central Thailand
Date: 2010
Source: Muang Boran Journal
Language: Thai
Notes: English Abstract: Promtin Tai is an Iron Age and Early Historic period site located in Lopburi province Thailand. Recent excavations by Dr. Thanik Lertcharnrit and Silpakorn University have uncovered Iron Age burials with ceramics, bronze and iron artifacts, and stone and glass beads. Almost 1000 glass beads and artifacts were found during the 2007 field season and twenty-three glass beads were selected for additional compositional analysis using Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) at the Field Museum in Chicago, Illinois. Most of the beads were small annular or globular monochromatic glass beads commonly described as Indo-Pacific beads. Results indicate that many of the glass beads found in burials were made from potash glass and mineral soda glass with variable amounts of alumina and lime. A smaller quantity of beads were made from high-alumina soda glass. In addition to Indo-Pacific beads, there were also more unusual bead types including glass beads that were made to imitate agate or onyx stone beads, gold-glass beads, and faience beads. The glass bead evidence from Promtin Tai highlights its importance as a transitional site from the late prehistoric into the Early Historic period. The diversity of glass beads and glass types found at the site underscore its connectedness to multiple trade networks. The stone beads at Promtin Tai are made from a variety of materials including agate, carnelian, as well as greenstone beads that may have been made from nephrite. The greenstone beads come in a variety of shapes and sizes, including bead shapes that we do not find in agate or carnelian. The origin of the nephrite beads is still unknown, however there are similar beads at other sites in Central Thailand. The origin of the agate and carnelian beads has also been the source of much speculation. Some of the agate and carenlian beads at Promtin Tai look similar in style and manufacturing method, specifically the drilling technique, to those found during the same time period in South Asia. However other scholars have wondered if some of these beads were made in Southeast Asia (e.g. Theunissen et al. 2000). Investigation of this question is ongoing, using LA-ICP-MS to analyze both stone beads and geological sources from across South and Southeast Asia. Preliminary results show that most of the beads from Promtin Tai are compositionally consistent with the Indian agate sources. This strongly indicates that the beads were being imported from South Asia, and not being made in Thailand. However there are a few beads that do appear to be compositionally distinct from the Indian sources. The meaning of these distinct beads is still unclear, however future research should help determine if some stone beads were being manufactured in Southeast Asia.
Date Created: 3/25/2014
Volume: 35
Number: 4
Page Start: 53
Page End: 68