TRACE ELEMENT CHARACTERIZATION OF DISTINCT OBSIDIAN FLOWS WITHIN THE COSO VOLCANIC FIELD, CALIFORNIA BY LASER ABLATION ICP/MS AND ARCHAEOLOGICAL IMPLICATIONS
We examined obsidian from Joshua Ridge, West Sugarloaf, Sugarloaf Mountain, and West Cactus Peak by Laser Ablation ICP/MS. This technique allows for quick and non-destructive trace element analysis of obsidian and other solids making it a promising tool for archaeogical investigations. Obsidian samples were analyzed for a suite of 25 trace elements including rare earth elements. The samples exhibited a generally similar trace element composition but differences in Rb, Ba, Zr, Sr, Ce, Dy, Eu, and Sm were large enough to allow distinction of the different source areas. An attempt was also made to distinguish obsidian from four different quarries on Sugarloaf Mountain. However, the composition of obsidian from these quarries was too similar to allow unequivocal identification.
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