PREHISTORIC CHERT QUARRIES IN OAXACA, MEXICO AND IMPLICATIONS ON STONE TOOL PRODUCTION: A GEOCHEMICAL APPROACH

This study focuses on chert resources found in the Mixteca Alta, a region in Oaxaca, México. Chert or more commonly known as flint, is a rock type that has widely been used in prehistoric times to craft tools. Obsidian is a better quality material and was preferred. However, accessibility to obsidian was limited and chert was used as a replacement. This study aims to determine differences in chert deposits near Pueblo Viejo, a prehistoric archaeological site that ancient people inhabited between 200 and 1400 A.D. At this moment in Mesoamerican history a kind of commerce super highway had already been established linking diverse groups from many regions of México. Attention was drawn to Oaxaca because of the unique geographic location linking the major regions of the Basin of México, Gulf Coast, Chiapas, and highland Morelos. This attention and importance is seen in one of the most famous Mesoamerican archaeological sites Monte Albán and associated sites such as Pueblo Viejo. Archaeologists working at Pueblo Viejo have excavated volumes of artifacts including obsidian and chert tools. Deposits of obsidian are not found locally, but chert deposits are ubiquitous in the Mixteca Alta. Chert is approximately 96–99.99% silicate (SiO2), no doubt existing differences will be on an extremely small scale. This study employs geochemical techniques including electron microprobe, hydrofluoric acid treatment, and isotope analysis to identify what the other 0.01-4% constituents are. Combining results from these techniques, unique characteristics corresponding to a deposit can be ascertained. If differences between chert deposits can be determined, then it is possible to locate where a chert artifact originated from.