Natural Science in Archaeology

4.4 Obsidian 87
major obsidian deposits of Europe and Anatolia, respectively. In Transcaucasia just
east and northeast of Anatolia, there are major obsidian deposits at Dogubayatzit,
Satanakar, Gutansar/Atis, Arteni, and in Georgia (Pernicka et al. 1996).
Obsidian was equally important in New World contexts. Indigenous miners in
Central America even pursued high-quality obsidian at depth, developing underground
mines. The Aztecs used obsidian extensively for projectile points, knives,
razors, swords, mirrors, and ornaments. There are numerous high-grade obsidian
deposits in western North America, such as Obsidian Cliff in Yellowstone National
Park, Wyoming, and in the volcanic regions of Central America. The Obsidian
Cliff source is one of the most famous obsidian localities in North America. This
180,000-year-old flow has been the source of obsidian for more than 10,000 years
and has been widely traded. Archaeological survey has identified 59 separate quarries
in the rhyolite plateau (Davis et al. 1992).
The major element composition of the Obsidian Cliff flows appears to be homogeneous,
regardless of color. Hughes (1993) has investigated the trace-element
variabilities in the flows. In the southwest USA, many obsidian deposits were
exploited by the indigenous peoples. Figure 4.12 shows the major obsidian flows in
this region. Glascock (1994) has reviewed recent work on obsidian in Mesoamerica.
See also Sheets et al. (1990) for obsidian sources in southern Mesoamerica and the
northern intermediate area. In South America, a quarry on the slopes of the Cotallalli
volcano in the south-central Andes has supplied obsidian for a large region for at
least 4500 years (Brooks et al. 1997).
The interest in obsidian and the success in provenancing archaeological obsidian
have led to literally hundreds of studies since the 1960s. Some investigations have
Fig. 4.12 Major obsidian deposits of the southwestern USA