Awareness and Protection of Prehistoric Resources
Many of the obsidian sources listed here are associated with the prehistoric procurement of natural glass. Please do not collect artifacts at these sources. This may not only be illegal (active prosecution of artifact collectors has proceeded with increased aggressiveness in recent years in the United States) but irrevocably erases and destroys the archaeological history of these significant areas. Strict limits on the amount of geologic material removed may be maintained and collection permits may be required for obsidian found on public lands (inquire locally). Please limit flintknapping activities to well-recognized areas so that the archaeological record remains as undisturbed as possible.

Acknowledgements
We would like to thank M. Steven Shackley (University of California, Berkeley), John D'Auria (Simon Fraser University), Fred Nelson (Brigham Young University), and Joe Moore (Nevada Department of Transportation) for their contributions of time, information, and text. Many of the Southwest United States and northern Mexico source lists are linked directly to descriptive information located at M. Steven Shackley's XRF Lab Web site at the University of California, Berkeley. Credits for individual source descriptions appear at the bottom of the description pages.

Caveat Emptor - The obsidian source catalog is a work in progress
Please keep in mind that the obsidian source catalog project provides only a snapshot of what remains a moving target - geoarchaeological and geochemical investigations of obsidian sources and artifacts are an area of active research and new sources are being located, relocated, and geochemically identified on a regular basis. The catalog listings available here are still somewhat preliminary and may be incomplete and unfinished. Some of the sources shown may simply represent duplicate names of known or listed sources; other sources are as yet unverified and may or may not exist. We continue to systematically review and refine the different lists - adding new sources, deleting nonexistent ones, combining multiple names for same sources, and more carefully distinguishing among the different geochemical source groups.