P-XRF compositional analysis of obsidian from O Block Cave, New Mexico

In 1952 Paul Sidney Martin and John Beach Rinaldo conducted excavations in O Block Cave located in west-central New Mexico. For the last 65 years, the collections from that expedition have been housed at the Field Museum of Natural History in Chicago. The focus of this study is to examine the obsidian artifacts collected during the O Block Cave investigation with a Niton Goldd+ portable x-ray fluorescence (p-XRF) device and determine geological origins. We contextualize the compositional results and the changes in obsidian exploitation patterns in the context of shifting regional social practices during the cave's 1100 years of intermittent use and occupation. These findings illustrate the utility and new insights gained when materials from extant museum collections are re-examined using new technologies.