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- Government Mountain Obsidian
Description: Government Mountain obsidian comes from the slopes of Government Mountain in the San Francisco Volcano Field near Flagstaff, Arizona. The material is fine-grained and generally lacking phenocrysts, but appears granular because of the presence of alkali feldspar in the matrix. - Partridge Creek Obsidian
Description: Partridge Creek, or Round Mountain, obsidian is found in the Mount Floyd volcanic field in southwest Coconino County, Arizona on the southeast flank of Round Mountain and in secondary deposits along Partridge Creek. The cortex of this obsidian ranges from gray-black to brown-black. The matrix is very glassy and typically opaque black, but thin flakes are cloudy gray and sometimes have cloudy banding. - Presley Wash Obsidian
Description: Presley Wash obsidian is actually a sub-vitreous rhyolite ranging from black to gray-green to opaque gray. Sanidine phenocrysts are often present in the matrix, as seen in both samples depicted here. The source of this material is in Presley Wash, east of Round Mountain, Arizona, and in the alluvium south of the juncture of Partridge Creek and Presley Wash in the same area. - Presley Wash Obsidian Biface
Description: Large Presley Wash obsidian biface alternately identified as Clovis, non-Clovis Paleoindian, and Pueblo in origin. Dimensions: 14.9 x 6.4 cm. Collection: On display at the Tuzigoot National Monument Visitor Center (catalog card). - Jay Point
Description: Jay point made on Government Mountain Obsidian. The point has a slightly contracting stem and a convex base. Dimensions: 4.32 x 2.22 x 0.7 cm. Collection: On display at the Tuzigoot National Monument Visitor Center (catalog card).