Reconstructing an ancient technology ANY OVERVIEW OF PREHISPANIC SOCIETY in the Americas would identify its obsidian core-blade production as a unique and highly inventive technology. Normally termed prismatic blades, these long, parallel-sided flakes are among the sharpest cutting tools ever produced by humans. Their standardized form permitted interchangeable use, and such blades became the cutting tool of choice throughout Mesoamerica between 600 and 800 B.C. Because considerable production skill is required, increased demand may have stimulated the appearance of craft specialists who played an integral role in Mesoamerican society. Some investigators have argued that control over obsidian also had a significant effect on the development and organization of chiefdom and state-level societies. While researchers have long recognized the potential of obsidian studies, recent work has focused primarily on compositional analysis to reconstruct trade and distribution networks. Study of blade production has received much less attention, and many aspects of this hig