In other words, as the rate of import increases, the proportion of the obsidian assemblage that is green decreases.
The obsidian cobbles are easily detached from their parent rock by water erosion and carried downstream.
The former were possibly the same individuals who exchanged the green obsidian to small centers and then to small sites.
Unworked and worked shell ornaments, shell "trumpets," and several clusters of obsidian projectile points were distributed following symmetrical patterns, mainly along the periphery.
The majority of the skull burials contain fewer than three objects, and only three of the 11 contexts contain obsidian.
Not smooth but rather marred by dense, small pockmarks; its par ticulate inclusions are finer and denser than those of any other obsidian sources.
Table 3 shows the quantities of transparent green obsidian versus graystriated, clear gray, and black obsidian found at each of the three frontier sites.
The inclusion of more information on the other techniques that are applicable to obsidian studies would have been very useful.
