Obsidian use in Mesoamerica

Obsidian was an important part of the material culture of Pre-Columbian Mesoamerica. Its uses, value, production, trade, sources, and analysis are all important aspects of the study of cultures in this region.

Practical and Ritual Obsidian Use

Almost no site in Mesoamerica is without obsidian, called "Itztli" in the Nahuatl language. It was an item that had both frequent, common uses and ritual use. Obsidian was available to all households and was found in hunting, agriculture, and many other everyday situations. Examples of possible obsidian tools are knives, lance and dart points, prismatic blades sometimes used for woodworking or shaving, bone working tools, bifaces, retouched flakes, and spearheads for ritual warfare. Blades have been found in situ with rabbit, rodent, and mollusk remains, indicating use in butchery.

Obsidian was also used in graves, at sacrifices, and in art. Some non-utilitarian forms are miniature human effigies, ear spools and labrets with gold and turquoise workings, carved animal figurines, beads, vases, and masks. Obsidian is frequently seen in the form of ritual blood-letting devices as well as buried in elite tombs and special deposits or caches. Debitage is found in many of these tombs in addition to evidence of obsidian use in temple dedications, potlaching, or offerings. For example, flakes have been found in association with stela offerings and related to specific gods at the Maya site of Tikal. Lancet and prismatic blades are also found in frequent association with self-sacrifice. Obsidian was a highly integrated part of Mesoamerican daily and ritual life. This widespread and varied use may be a significant contributor to this culture's lack of metallurgy.

Value

Obsidian was widely distributed throughout Mesoamerica by trade. Its importance to Mesoamerican societies has been compared to the value and importance of steel to modern civilization. However, archeological evidence provides varied evidence of the individual value placed on obsidian. For example during the Formative period, obsidian was a rare item in the lowland areas, found predominately in elite and ritual contexts. In many Maya excavations evidence of obsidian is likewise found most frequently in privileged settings; as the Late Classic period progressed, obsidian changed from an elite item to one found in abundance among the lower classes of Maya civilization. Nevertheless, the Maya elite continued to remain in possession of the more prestigious Teotihuacan green obsidian.

In the Teotihuacan culture obsidian was perhaps traded at a loss of human effort in transport across long distances. The profit from the trade was prestigious elite items received in return. Obsidian has both been seen as a key element to Teotihuacan's rise to power and as a side trade element that simply augmented their already developing wealth. Obsidian is a part of many elite items such as valuable ear-spools, but these obsidian ear-spools have been discovered in exclusively non-elite settings. Thus the value of obsidian can be considered highly variable. It was an important trade item, but found in both elite and common settings, unlike many items whose ownership was confined to the elite. Finally, there is no indication that obsidian was used as a currency in Mesoamerica.

Production and Techniques

Obsidian is relatively easy to work, aiding its prolific use throughout Mesoamerica. Obsidian is obtained by quarrying a source site. Pieces then are shaped by fracture as in the production of blades or knives. It may be also be formed by pecking and grinding, producing animal figurines, beads, labrets, ear ornaments, and other erratics. Pressure flaking blades from a prepared core was a common practice. Edge-rejuvenation or resharpening of blades was performed to prolong the lifespan of many pieces. Modern attempts to recreate production techniques are heavily based on Spanish records and accounts of obsidian knapping. Motolinia, a Spanish observer, left this account of pressure flaking: "It is in this manner: First they get out a knife stone (obsidian core) which is black like jet and 20 cm or slightly less in length, and they make it cylindrical and as thick as the calf of the leg, and they place the stone between the feet, and with a stick apply force to the edges of the stone, and at every push they give a little knife springs off with its edges like those of a razor."*

The widespread use of obsidian necessitated a large workforce to produce enough tools to supply an area. During Monte Alban's most populous period 900 to 1800 people were working obsidian. In Teotihuacan, a major contributor, if not possessing monopolistic control of obsidian trade and production, possessed more than 100 obsidian workshops within the city.

Trade

Obsidian sources are relatively easily identified through trace chemical element analysis, making obsidian an excellent medium for the study of long-distance trade in Mesoamerica. This pan-Mesoamerican trade industry is due to the limited number of quality sources; the low bulk of obsidian in transport, thus requiring less human effort in trade; and the large quantity of items that may be produced from that small amount. Two cultures are good examples of the source side of trading and the recipient side; Teotihuacan held significant control over major obsidian sources, and the Mayan culture did not control a single significant source. Evidence of Teotihuacan's trade strength is seen in the presence of obsidian artifacts originating from their controlled sources throughout Mesoamerica, even at a distance of over 350 miles. It is debated whether the rise of this culture's dominance came from obsidian trade or if the trade simply served as a mode for obtaining elite items or human labor. The Maya acquired their obsidian from long-distance trade arriving at central places such as Tikal, Uaxactan, and Palenque. These Maya centers then redistributed the obsidian to smaller settlements. This is seen by the lack debitage from core production, cortex flakes or large percussion flakes, in the more rural areas of Maya territory. The larger centers may have exported fully pre-formed cores to outlying regions. Evidence also points towards much coastal trade, with higher quantities of obsidian artifacts found in coastal sites than in those farther inland in areas such as Belize. Obsidian trade was far-reaching, allowing opportunities for contact and trade of a variety of other items and ideas during pre-Hispanic times.

Sources

Obsidian sources were limited in Mesoamerica. Principal sources in Mexico included Jalisco, Oyameles, Zaragoza, Guadalupe Victoria, Cerro de Minas, Cerro de las Navajas, and Ucareo, the post-classic source for the Toltec state. Sources in the Valley of Mexico and under Teotihuacan control were Pachuca, Otumba, and Chicoloapan. Pachuca was a notable source with its high quality green obsidian, which was traded widely throughout Mesoamerica. In Guatemala three sources were significant: El Chayal, Ixtepeque, and San Martin Jilotepeque. These highland Guatemalan sources served the Mayans through long-distance trade. The Olmec heartland and the Valley of Oaxaca are two significant locations that lack obsidian sources.

Chemical Analysis

Obsidian, a volcanic glass, comes from several geological sources in Mesoamerica, as listed above. Each of these sources has a distinctive “fingerprint” of trace elements of the chemicals in a particular obsidian sample. Neutron activity analysis and X-ray fluorescence are two methods of analysis to identify a sample's geological source. Dating analysis is also performed on obsidian artifacts. Hydration dating permits absolute or relative dating of a sample. The degree of hydration observed indicates how long it has been since an artisan exposed the obsidian surface. All of these analysis techniques are invaluable for obsidian production and trade studies in the region.

Cited Resource

• Hester, Thomas R., Jack, Robert N., and Heizer, Robert F. The Obsidian of Tres Zapotes, Veracruz, Mexico. University of California Archeology Research Facility. No. 13 pp. 65-131, 1971.