Jade, amber, obsidian and serpentinite : the social context of exotic stone exchange networks in central Japan during the Late Middle Jômon period
This dissertation presents a holistic, contextual approach to long-distance exchange networks in Central Japan ca. 4000BP, by focussing on the conditions behind consumption, circulation and production of exotic materials-particularly jadeite and amber, derived from unique and spatially limited source areas: the Japan Sea Coast and the Pacific Coast, respectively. Analysis is based on a sample of 175 sites located in Nagano, Yamanashi, Tokyo, Kanagawa and Chiba prefectures. Analysis of consumption patterns shows that (compared to other artefact categories) stone ornaments, particularly jadeite and amber pendants, are far more frequently associated with 'intentional deposition', namely mortuary contexts. This indicates that a different value was ascribed to jadeite and amber pendants. However, other evidence of social differentiation during the Middle Jômon is absent. Statistical analysis of wider distribution patterns, focusing on the variability of site characteristics, supports the hypothesis that the presence of jadeite and/or amber pendants is strongly associated with 'core' settlements sites characterised by large house numbers, continuous habitation throughout the Middle Jômon period, and evidence of ritual practices. Contrary to some hypotheses, evidence for related distribution between jadeite pendants and serpentinite adzes (from the same production sites) was lacking, whereas association with relatively high quantities of obsidian (used for arrowheads) proved to be strong. It is suggested that exploitation and export of nearby high-quality obsidian resources contributed to the prosperity and longevity of Japan Alps settlements. In the greater Tokyo Plains area, settlements stable and influential enough to participate in the exchange networks are located at major rivers or coastal areas. Preliminary assessment of the conditions at production sites suggests different motives for part-time ornament production. It is hypothesised that inhabitants of the Japan Sea area-a hostile and isolated environment-may have engaged in fairly regular production and export of jadeite pendants and serpentinite ground adzes, in order to maintain interregional relations, possibly as a socio-economic safety net. Perhaps-in the absence of obvious environmental or subsistence constraints-Pacific Coast inhabitants produced amber pendants occasionally, exchanging them as hunting amulets between specialist hunters. However, further research involving subsistence patterns is essential for a deeper understanding of long-distance exchange network membership. Finally, it is suggested that instead of being individually-owned valuables, jadeite pendants (as 'esoteric', inalienable items) circulated among certain settlements in an interregional exchange network, regulating relationships and creating a social context for different types of exchange. Perhaps mortuary contexts indicate exchange relations with 'the other world'.