Within the larger survey area, the radial attenuation pattern of obsidian artifacts around the Chivay obsidian source is a common characteristic of single-point raw material sources. This attenuation resembles a distance-decay pattern, but on a local scale. Obsidian artifacts dominate the assemblages in Survey Blocks 1, 4, and 5; the ones that are adjacent to Chivay source, while locally available chert and quartzite are well-represented in assemblages in Block 3, the upper Colca river valley. The impetus for quarrying in the Maymeja area appears to have been driven by a demand for larger obsidian nodules, and for obsidian material with few heterogeneities. Complete artifacts with > 30% cortex, including tools, flakes, and cores, were considerably larger in Block 1 than in other blocks. In surface assemblages in Block 2, which lies the same distance from the Chivay source as Block 3, obsidian dominates the lithic artifacts and andesite and other fine-grained volcanics are also present. On the surface of Blocks 1, 4, and 5, close to the Chivay source, obsidian cores and cortical flakes are more common, and in Blocks 1 and 5 bifacial thinning flakes (BTF) were relatively common with the highest fraction of BTF being located at the site of A03-910 in Block 5.
Earlier it was noted that there was variability in obsidian knapping quality both in original geological exposures and in artifact materials. Obsidian containing heterogeneities such as air bubbles, ash particles, fractures, and occasionally inclusions, were observed in different areas of the Chivay source. While the majority of tools were produced on homogeneous glass (referred to here as "Ob1"), a substantial fraction of flakes and cores, and some tools, were observed in the "Ob2" material containing heterogeneities. When the Ob2 heterogeneities are very small, the knapping quality of the material appears to have not been compromised albeit the material is visibly less pure. A large percentage of the flakes in Block 3 were Ob2 obsidian, while all of the projectile points made from Ob2 obsidian were found in Block 2 in the high puna.
Visual characteristics of Chivay obsidian vary across the source area as well. Colors recorded for artifacts during the phase II lithics analysis included black, grey, transparent (clear), and dark banding was visible in grey and transparent obsidian. Banding resulting from concentrations of tiny magnetite crystals is common in light grey and transparent material. High numbers of transparent flakes were encountered in Block 1 and Block 2, which is along the direct route from the Chivay source to the Lake Titicaca Basin where obsidian from the Colca is known as the "transparent type" (Giesso 2003). Obsidian color and translucence was difficult to quantify during lab analysis, and it is possible that the distinction between grey and clear obsidian may be connected to flake thickness where thinner flakes appear to be less grey due to greater quantity of light passing through.