The Elmenteitan Obsidian Quarry (GsJj50): New Perspectives on Obsidian Access and Exchange During the Pastoral Neolithic in Southern Kenya

Early pastoralists in southern Kenya exploited obsidian sources to supply large regional exchange networks that persisted from c. 3200 to 1400 years ago. Obsidian exchange networks have been a source for speculation on the social and political nature of early pastoralism in eastern Africa. Herders who produced a discrete set of material culture called “Elmenteitan” mainly relied on a particular obsidian quarry site on the upper slopes of Ol Doinyo Opuru (Mt. Eburru), in the Central Rift Valley. These implications of the Elmenteitan pattern for herder social organization have not been systematically investigated. This paper reports on recent surveys and initial excavations at the Elmenteitan Obsidian Quarry (GsJj50) on Mt. Eburru as the central node of a prehistoric herder exchange network. Research revealed a series of stratified extraction and workshopping loci concentrated across a roughly 200-m² extent. Spatial, faunal, ceramic, and lithic datasets support communal resource access by small groups, rather than centralized control. This research has implications for interpreting the role of centralized quarries and resource nodes in the formation of mobile herder exchange and alliance. Networks were an important risk-reduction strategy in unpredictable environments and helped facilitate the spread of African pastoralism.