T. P. Miller W. W. Patton Jr. 1970 Recently discovered deposits of obsidian in the Koyukuk valley may be the long-sought-for source of obsidian found in archeological sites in northwestern Alaska. Obsidian from these deposits compares favorably in physical characteristics and sodium-manganese ratio with the archeological obsidian, and there is evidence that the deposits have been "mined" in the past. application/pdf 10.1126/science.169.3947.760 en American Association for the Advancement of Science A possible bedrock source for obsidian found in archeological sites in northwestern Alaska article