Obsidian Studies in the Truckee Meadows, Nevada

The Truckee Meadows is a well-watered valley in western Nevada with archaeological evidence of aboriginal human occupation extending from 150 B.P. to about 10,000 B.P. Obsidian samples from 27 archaeological sites in and around the Truckee Meadows (401 individual specimens) have been analyzed for geochemical source determination, and 183 of these obsidian specimens have been analyzed for hydration rind thicknesses. A total of 20 different obsidian sources in seven distinct geographic localities is represented in the combined obsidian samples. Despite this great diversity, 46% of the sample obsidian was derived from local sources, while 38% was derived from the Mono Basin in southeast California. The remainder of the sample obsidian (16%) was derived from sources scattered throughout northeast California and northwest Nevada, as well as from several unidentified sources. No temporal trends or shifts in the utilization of particular obsidian sources are apparent in the sample. Hydration rind thicknesses vary from 0.8 to 9.8, but the data for Sutro Springs obsidian suggest that hydration rind thickness is an unreliable technique for determining the age of obsidian artifacts, whether relative or absolute