Journal of California and Great Basin Anthropology

In this paper we have reported upon the discovery of a cache of 16 obsidian bifaces derived from the Mount Konocti obsidian source. We have suggested that this cache dates to the start of the Dry Creek Phase thought to mark the arrival of the ancestral Pomoan people west of the Russian River Valley. The Caballo Blanco Biface Cache provides a rare view into the Mount Konocti obsidian exchange system just as it began a rapid expansion roughly 2,500 B.P. Single events are rarely documented archaeologically in the North Coast Ranges and, generally, obsidian chipping debris represents patterned behavior by numerous individuals over long periods of time. The Caballo Blanco Biface Cache represents specific behavior culminating at an instant in time.