Skip to main content

Indigenous-led investigations of ancient lithic resource use in the Pacific Northwest: extensive volcaniclastic toolstone sources (re)discovered in Sts’ailes territory, southwestern British Columbia

Thursday 8 October, 4 PM CET (AMGC)

Dr. Rhy McMillan

BIO: Rhy McMillan (PhD, Geological Sciences) blends geochemistry and archaeology in his quest to create equitable partnerships with Indigenous communities and produce additional lines of archaeological evidence in collaboration with oral history and Indigenous science. As a multidisciplinary researcher, Rhy uses Western scientific techniques to investigate the sedimentary context of archaeological objects, their preservation states, their geochemical characteristics, and the degree to which they have been physically and chemically altered post-mortem and/or post-burial. 

ABSTRACT: As a Social Sciences and Humanities Research Council of Canada (SSHRC) Postdoctoral Fellow, currently Rhy’s main goal is to overcome the paucity of information on toolstone sources used by ancient Indigenous peoples in the Pacific Northwest (PNW), who relied on fine-grained geologic materials for a range of tool technologies. However, very little is known about most of the contexts from which such archaeological toolstone materials originated. This is a result of limited efforts to identify and sufficiently characterize toolstone sources and quarries, compounded by only using a single line of evidence (e.g., trace element concentrations) in sourcing studies. These factors thus severely limit interpretations of ancient landscape use, tool production, and exchange. In partnership with Indigenous knowledge holders and archaeologists, Rhy is addressing these challenges by examining one of the most complex toolstone contexts yet identified in the region, the Harrison Lake Formation in Sts’ailes territory (British Columbia). Rhy and his collaborators have conducted systematic fieldwork and geochemical investigations to establish the nature and distribution of the toolstone-grade facies outcropping throughout the territory. Preliminary results indicate that people quarried this volcaniclastic chert (metasomatized tuff) from numerous sites, and it is common in archaeological assemblages but undocumented in the literature. The material is typically cryptocrystalline, structurally homogenous, and occasionally contains sulphide minerals and glass fragments. It is basaltic to rhyolitic in composition and has trace element concentrations that span almost the entire range of other documented coastal lithic sources, prompting re-investigation of the origins of archaeological materials, and thus ancient Indigenous landscape use, in the PNW.