Geologic provenience analysis of agate and carnelian beads using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS): A case study from Iron Age Cambodia and Thailand

Abstract

13 Agate and carnelian beads, imported from South Asia, were widely exchanged in Southeast Asia 14 during the Iron Age period (500 BCE -500 CE). Recent studies have identified changes in bead 15types and manufacturing methods over time, as well as evidence for possible local production. In 16 order to understand the broader implications of these developments, geochemical analysis using 17 laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) was undertaken on 18 73 beads from 10 Iron Age sites in Cambodia and Thailand and 64 geologic samples from four 19 sites in India, Iran, and Thailand. The results show that many of the beads were produced from 20 raw material derived from the Deccan Traps, India and that there is not yet strong evidence for 21 bead production using a Southeast Asian source. Secondly, we find that there is not yet clear 22 evidence for a change in the different geologic sources used to produce beads over time. This 23 study adds to the growing body of literature highlighting the utility of LA-ICP-MS in 24 differentiating and assigning provenience to agate/carnelian and other silicates.

On-Site Raman Spectroscopic Study of Beads from the Necropolis of Vohemar, Northern Madagascar (>13th C.)

“…Carnelian and rock crystal beads are shaped, spherical or faceted: termed bi-conical, bitronconical, pear-shaped, lozenge, faceted tabular according the classification by Beck [29] and taken up by Dubin [30]. Carnelian and agate beads were produced in India and Pakistan and traded very early across the Indian Ocean [31][32][33][34][35][36][37]. According to Rasoarifetra, worked patterns [18] including the faceted type are characteristic of the production at the Indian city of Cambay [9,[31][32][33][34][35][36][37], the facets giving the stone a particular sparkle.…”

“…Carnelian gems have been used since antiquity [56,[60][61][62][63] and sources are rather well documented for the Mediterranean world [60] and for India [1,2,[32][33][34][35][36]. The moganite peak has not been reported previously.…”

Glass ornament production and trade polities in the Upper-Thai Peninsula during the Early Iron Age

“…As in the case of hard stones (Bellina, 2007(Bellina, , 2014 and possibly of copperbased industries , the sudden appearance of complex skills necessary for the production of glass ornaments at Khao Sam Kaeo suggests a transfer of artisans, likely from India. Again, as for siliceous stones which were most likely imported from India (Carter and Dussubieux, 2016), raw glass found at Khao Sam Khao was imported from India through the Bay of Bengal Interaction Sphere to be locally transformed into ornaments with a style shared by communities of the South China Sea Interaction Sphere within which they were then "distributed" as far as the Philippines (Dussubieux and Bellina, 2017).…”

Development of maritime Trade Polities and diffusion of the “South China Sea Sphere of Interaction pan-regional culture”: The Khao Sek excavations and industries' studies contribution

“…Except for Sa Huynh-Kalanay ceramics, those goods were interpreted as mere imports until a decade ago when technological analysis began to suggest that some of the emblematic ones, the hard stone ornaments, were made locally with foreign techniques and adapted to local taste (Bellina, 2001(Bellina, , 2007. Since then, research has generated increasing evidence that these widespread objects were most often locally made, combining imported motifs and shapes (Flavel, 1997), exotic materials (Carter, 2015;Carter and Dussubieux, 2016;Hung and Bellwood, 2010;Hung, in press) and skilled exogenous techniques that originated in South Asia and East Asia (Bellina, 2001(Bellina, , 2003(Bellina, , 2007Bellina et al, 2012;Bouvet, 2011;Dussubieux and Bellina, in press;Favereau, 2015;Favereau and Bellina, 2016;Pryce et al, in press). The hybrid nature of these products reveals that social and political interactions within and between societies of the two sea basins during late prehistoric periods were much more complex and dynamic than expected.…”