Chemical Sourcing of Obsidian Artifacts from the Grissom Site (45-KT-301) to Study Source Variability

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Anthropology and Museum Studies

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The Grissom site (45-KT-301) is a late Holocene archaeological deposit in northeast Kittitas County, Washington. Ethnohistoric and historic evidence indicates that the site may reside near the historically recorded Kittitas Fair, or Che-lo-han, a gathering place for Native Americans. Given the proximity to a trade center and the presence of obsidian artifacts, the site exhibits potential to contribute information on obsidian movement and trade in the Pacific Northwest. Using an evolutionary archaeology framework, we undertook a systematic lithic analysis of 167 obsidian artifacts from the Grissom site, including an XRF analysis of a 30% sample. The purpose of this research was to identify whether the site may have been at or near a trade location, and to quantify relationships between source diversity, source locality, and lithic technology. We then compared the results to four previously identified patterns or models for Pacific Northwest obsidian artifact distribution. Eight nonlocal sources and two local sources were identified in the study, supporting the possibility that the site may have been located at or near a trade center. The source diversity in obsidian bifaces and flakes was found to be significantly higher than that of cores, most of which were from a local obsidian source. An inter-site comparison between the Grissom obsidian and the obsidian from three southern Cascade Mountain sites suggested that site-to-source distance was not the only factor driving obsidian occurrence, and instead source quality, trade relationships, or other influences likely contributed to obsidian source distribution at these sites.


This article was originally published in Journal of Northwest Anthropology. The full-text article from the publisher can be found here.

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Journal of Northwest Anthropology


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