Introduction The Zaragoza-Oyameles obsidian source area in northeast Puebla, Mexico was a major source of obsidian in western Mesoamerica from the Late Formative through Late Classic periods (ca. 400 B.C. – A.D. 900). Due to the traditional focus on obsidian consumer sites in prehispanic Mesoamerican archaeology however, little is understood about how obsidian extraction and production systems were organized, how these systems were linked to regional and interregional obsidian economies, and, ultimately, what the nature of their role in regional sociopolitical behaviors was. To begin to address these questions a fundamental base-line of data from the source area is needed. Therefore, one goal of the Zaragoza- Oyameles Regional Obsidian Survey, Puebla, Mexico project has been to create detailed representations of obsidian quarries in order to gauge the volume of obsidian extracted and ultimately arrive at a gross estimation of the quantity of obsidian commodities produced at each quarry. This information will be compared to the data that is currently being generated on the quantity and types of reduction debris collected and analyzed at adjacent reduction sites and at more distant non-quarry sites. In order to achieve this goal, a program of intensive systematic surface survey and collection was undertaken at the Zaragoza-Oyameles source area in the spring of 2012 and 2013, including a program of intensive topographic surface mapping of selected extraction locales (Figure 1). Methods The surface survey comprised seven archaeologists walking along parallel transects spaced 5 m apart in plowed fields (Figure 2). All surface tools, such as projectile points, cores, bifaces, and scrapers, as well as all ground stone and ceramics were marked with a hand-held Garmin 62s GPS and then collected. Once identified, sites were either 100% surface collected or by a 10% random sample of 5 x 5 m surface units, depending on site size (Figure 3). In forested regions and stream-bed slopes archaeologists walked parallel transects 10 m apart following cardinal directions. After the 2012 and 2013 field seasons, a total of 2,901 acres have been intensely surface surveyed, resulting in the identification of 44 reduction sites, 2 habitation sites,152 obsidian exposures, 77 surface extraction pits, and 3 trenches (Figure 4). Acknowledgments The Zaragoza-Oyameles Regional Obsidian Survey, Puebla, Mexico project is generously supported by a National Science Foundation Senior Research Grant (BCS-1063233). Also, Northwest College funded four Anthropology students to participate in project mapping. Estimating Extraction Extraction Area 34 is well defined and contains an exposed section of spherulitic obsidian banding approximately 1 m thick along its southeastern edge (Figure 5). The extraction pit measures approximately 23 x 20 x 3.2 m in size (Figure 6). Our calculation of the volume of extracted material recognizes the influence of several unknown variables. First, the amount of post-abandonment in-filling of the extraction pit over the centuries is not known, but may be considerable due to the heavy deforestation in the area and the location of the extraction pit at the base of a steep slope. Second, the proportion of non-tool quality obsidian and non-obsidian material extraction may never be known and therefore is estimated conservatively. In order to calculate the extracted volume of material at Extraction Area 34, the extraction pit was isolated or “blanked out” from its adjacent topographic context in SURFER using “0” as the default upper grid, which corresponds to the natural surface of the area surrounding the pit (Figure 7). The lowest point taken during mapping of the pit was -3.2 m, and this was used as the bottom grid. Using the VOLUME command in SURFER, the volume of material removed from Extraction Area 34 was determined to be 331 m 3 . Results Obsidian debitage identified on the surface of Extraction Area 34 indicated that blocks of obsidian were being extracted in order to fabricate macrocores and large polyhedral cores. Large macroblades, macro-ridge blades and macroflakes were identified on the surface of the workshop, including the largest macrocore blades found thus far (Figure 8). Mapping Obsidian Extraction at the Zaragoza-Oyameles Obsidian Source, Puebla, Mexico Charles L. F. Knight (University of Vermont) and J. Gregory Smith ( Northwest College) Literature cited Pastrana, Alejandro 1998 La explotación azteca de la obsidiana en la Sierra de las Navajas. Serie Arqueología, Instituto Nacional de Antropología e Historia, México, D.F. Fig. 6. SURFER surface model of Extraction Area 34. Fig. 1. Limits of the 2012 and 2013 surveys and locations of selected features. Fig. 7. Extraction Area 34 SURFER contour (a), blanked contour of pit (b). Topographic Mapping A program of topographic mapping using a Nikon DTM-332 Total Station was conducted by Smith with assistance from Northwest College anthropology students. Mapping focused on known surface extraction pits. Most extraction pit complexes occur on slope, thus the surrounding slopes were mapped to contextualize the pits. In this manner, four surface pit complexes were mapped: Extraction Areas 2, 21, 23, and 34. Fig. 3. 100% Site surface collection (a), 5x5 m site surface collection (b). Fig. 2. Surface field survey. Fig. 5. Mapping Extraction Area 34. a b Fig. 4. Types of surface exposures. a b At the Sierra de las Navajas obsidian source in Hidalgo, Mexico, Pastrana (1998:81) has estimated that 2-10% of the material removed from surface pits was useable obsidian, the remainder being rhyolite, ash, lapilli and other volcanic material. As a result, 2-10% of the extracted volume results in 6.6 - 33 m 3 of usable obsidian from Extraction Area 34. Four macrocores recovered from the 2012 surface collections averaged 12.5 x 13.6 x 11.1 cm in size, and 1,887 cm 3 or .001887 m 3 in volume. Based on informal macrocore production experiments by Knight, an average of 20% of a cobble’s volume is removed in macrocore shaping. Utilizing this proportion, the average volume of an extracted cobble suitable to form a macrocore would be .002358 m 3 . This results in the potential for 2,799-13,995 obsidian blocks of suitable size for macrocore reduction to have been quarried from Extraction Area 34. Using a conservative estimate of 100 prismatic blades per prismatic core the prismatic blade potential from this extraction area is 279,900–1,399,500 prismatic blades, provided that no cores are ruined in the reduction process. The key unknown variable is the length of time that this extraction area was in operation. A one-year operation results in 233–1,166 macrocores per month or 7.7-38.3 per day, which seems high for anything other than organized full-time production by several producers. However, if we consider a 10-year period of exploitation, the results are 23.2-116.1 macrocores per year or 1.9-9.7 per month, which would be possible by several individuals working part-time. Fig. 8. Large Macroblades. 40 cm scale. Conclusions The data presented indicates that even when estimates of material extracted are conservative, a significant amount of macrocores and large polyhedral cores were produced at this location. While Extraction Area 34 is one of the best defined mid-sized quarry pits thus far identified, it represents only one of 77 such quarry pits known in the Zaragoza-Oyameles obsidian source area. As a result, we can begin to understand the overall amount of material extraction that may have been carried out at this source, the types of artifacts produced, and the intensity of extraction and production.