Obsidian Use in Mesoamerica - Sources

Sources

Obsidian sources in Mesoamerica are limited in number and distribution, and are restricted to the volcanic regions of the Sierra Madre de Chiapas Mountains as it runs through Mexico and Guatemala. These resources, however, are still quite abundant in the archaeological record and their origins can be traced by their physical and geological properties. Before discussing these obsidian sources, a definition of what an obsidian source is must be established, as many of the terms used allow for different and competing interpretations.

Sidrys et al. (1976) stated that an obsidian source area includes several outcroppings of obsidian, limited in spatial extent, which may or may not have common chemical features and may or may not have been used by ancient humans. Michael D. Glascock, of the University of Missouri Research Reactor Center at the University of Missouri (which performs neutron activation analysis), has divided Mesoamerica into nine sub-regions with one or more obsidian sources in each. These subdivisions, while effective at systemizing the source characteristics and allowing for a more easily visualized distribution of sources, are still tentative. They are as follows:

• Zaragoza (includes the Zaragoza and Altotonga quarries), in the south-central Gulf lowlands of Mexico)
• Orizaba (includes the Pico de Orizaba, Guadalupe Victoria, and Derrumbadas sources), in the south-central Gulf lowlands of Mexico
• Paredon (Paredon and Santa Elena sources), in the central highlands of Mexico
• Otumba (Otumba and Malpais), in the central highlands of Mexico
• Tulancingo (Tulancingo and Tepalcingo), in the central highlands of Mexico
• Pachuca (a number of different quarries), in the central highlands of Mexico
• Zacualtipan (Zacualtipan, one source only), in the central highlands of Mexico
• Ucareo (Ucareo and Zinapecuaro) - largest source in west Mexico (in Michoacán).
• The Guatemalan region – which incorporates all sources located in the Guatemalan highlands. Tajumulco, El Chayal, Ixtepeque, and San Martín Jilotepeque are the best known obsidian sources in Guatemala and were commonly exploited in Pre-Columbian Mesoamerica. In fact, almost all Obsidian found in Olmec and Maya sites originates from these sources.

Sources in the Valley of Mexico, which fell under Teotihuacan control during the Early Classic, were Pachuca, Otumba, and Chicoloapan. Obsidian from Pachuca is notable because of its unique green-gold color and its internal purity which makes it one of the highest quality obsidian sources in Mesoamerica. It was much sought after and widely traded. Green obsidian is also found in the area of Tulancingo, but is distinct from Pachuca obsidian because of its internal opacity (e.g., it is a more milky or clouded green).

Substantial research has been carried out to decipher the Guatemala region sources. As mentioned earlier, the Guatemalan region includes the El Chayal, Ixtepeque, and San Martin Jilotepeque sources, located in southern/southeastern Guatemala. Obsidian originating from Guatemala was widely used in Mesoamerica and is found as far north as the Yucatán Peninsula, moving via a well-developed long-distance trade network that inter-connected much of the Maya area. Newer and tentative additions to the Guatemalan source area are Jalapa and Sansare. However, the El Chayal area is often seen as subsuming these two into one large source area. The Pre Classic Monte Alto culture and Olmec cultures also used the Tajumulco Volcano source, in the southwest of Guatemala, a source that was almost forgotten during the Classic and Post Classic periods.