This preliminary typology of Aztec formal chipped stone tools was created taking into account the context in which the lithics were recovered, their morphology, and manufacturing processes. The typology defines six categories of stone tools: ornately decorated bifaces (this includes ceremonial lithic artifacts), projectile points, scrapers, perforators, denticulates, and other. The thesis also includes an analysis of 10 previously unanalyzed Aztec lithic assemblages. When taken together the typology and lithic analysis provide a summary description of the Aztec lithic industry. / by Timothy J. Guyah. / Thesis (M.A.)--Florida Atlantic University, 2012. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2012. Mode of access: World Wide Web.

Obsidian is one of the most common materials preserved in the archaeological record of Mesoamerica. Because of this and obsidian's unique chemical properties, it has become one of the most common means by which to explain ancient exchange and production. Northern Belize has largely been absent from discussions of Postclassic Mesoamerican economies. The limited amount of obsidian research that has been done is unable to draw comparisons to the region's primary site during this period, Santa Rita Corozal. This thesis remedies this by exploring the importation, production, and distribution of obsidian at the Postclassic Maya primary center of Santa Rita Corozal, Belize. Through the application of the lithic technology approach and the use of pXRF (portable X-ray fluorescence) spectrometry, it is possible to establish the sources of obsidian being exploited, the stage of reduction of obsidian imports, the major obsidian industry, and obsidian distribution for Santa Rita Corozal's Postclassic Period.

Obsidian source attribution has become an important tool in examining many aspects of prehistoric lifeways including exchange, identity, social and economic boundaries, and many others. This thesis provides a comprehensive look at obsidian spatial distributions in the Tucson Basin Hohokam Pre-Classic period, ca. A.D. 750-1150. By examining currently available data and providing new data from three sites in the northern Tucson Basin conclusions about trends in spatial and temporal use of obsidian are made. Obsidian procurement and spatial distribution in the Tucson Basin appears to be distinct from neighboring regions and continuity with later Classic period, ca. A.D. 1150-1450 obsidian use is likely. There appears to be a clear preference for western obsidian sources in the northern Tucson basin, while the southern basin may have a slight preference for materials to the east. The limited obsidian data for the Colonial period, ca. A.D. 750-950 suggests that its distribution was controlled by similar processes to those observed in the Sedentary period, ca. A.D. 950-1150. This research further suggests that strong avenues are open for future research.

Archaeological investigations at Edwards Air Force Base (AFB) have been ongoing for more than 40 years. Yet the findings from the vast majority of those efforts are available only as grey literature that is known only to a relative few. The primary purpose of this thesis was to investigate a late Holocene decline in obsidian frequency reported by researchers working in the Bissell Basin and Rosamond Dry Lake region of Edwards AFB near the turn of the 21st century. A secondary purpose of this thesis was to shine a light on an area of the western Mojave Desert that is not widely known despite more than four decades of research. In order to explore the reported decline in obsidian frequency, I created an obsidian database using data gleaned from nearly 50 cultural resources management reports and supplemented those data with sourcing and hydration information for 39 additional obsidian artifacts. Those data were organized into tables, charts, and histograms to look for patterns that would support or refute the claim that obsidian use decreased significantly after the Gypsum time period (4000 to 1500 Before Present [B.P.]). Two patterns emerged from my analysis. The first was one where the overall abundance of obsidian at Edwards AFB did not decrease during the late Holocene, thus contradicting the conclusions made in the previous research. The second was one where the obsidian abundance shifted among the various regions of the installation. Yet these shifts are nowhere near as significant as the previously reported decline. Therefore, while the total amount of obsidian that entered the archaeological record at Edwards remained relatively stable from 1500 to 100 B.P., the amount of obsidian decreased in certain regions and increased in others. Although not within the scope of my original intent, my research also identified two areas for future research. The first involves an apparent pattern where the number of archaeological sites from which obsidian was recovered gradually decreases during the middle-Holocene even as the overall quantity of obsidian remains essentially unchanged. The second relates to the lack of a well-established hydration rate formula for obsidian recovered from archaeological sites on Edwards AFB. Ultimately, I concluded that the previous findings that obsidian declined during the late Holocene were affected by sampling bias and faulty data organization. Most archaeologists understand that poorly implemented sampling can lead to poorly derived findings and conclusions. What may not be as well understood is that a perfectly appropriate sample where the data are not organized well can also lead to flawed results and conclusions. It is hoped that this thesis will inform archaeologists not only about how the manner in which they organize their data can affect their interpretation of past human behavior, but also about additional research opportunities at Edwards AFB.

The primary concern of this thesis is to quantify and analyze the lithic (chipped stone) assemblage previously excavated by Hepp (2015) and the La Consentida Archaeological Project (LCAP) at the archaeological site of La Consentida in the lower Río Verde Valley, Oaxaca, Mexico. The lithic assemblage is comprised of over 500 artifacts mainly of obsidian and chert. This research represents a study of all primary context lithic artifacts from La Consentida and focuses on obsidian, the material most used at the site. In the first part of this thesis I provide an analysis of all lithic artifacts of this primary context assemblage collected during the 2012 field season. Additionally, I present technological considerations regarding manufacturing techniques and subsequent issues regarding technique implementation. The second part of this thesis examines the distribution of lithics, in addition to other artifact classes (i.e. ceramics and ground stone), at the site and relates this to manufacturing techniques and inferences towards social organization. Results indicate that the people of La Consentida favored obsidian as a material for lithic manufacture. While other materials were used to produce chipped stone, obsidian dominates the assemblage. Further, these materials were used in expedient lithic reduction, which characterizes the majority of the assemblage. In addition to expedient flakes, specialized tools are also present, although minimal. Additionally, the way in which lithics, and more importantly obsidian artifacts, are distributed at the site indicates a purposeful designation for manufacture and use in specific locations. The artifacts I examine here are crucial to determining the economic practices of this Early Formative period (2000–1000 B.C.) site. Ascertaining how the lithic artifacts were distributed at the site will help expand current understandings of Early Formative period exchange, crafting, and subsistence practices. Furthermore, these results may have implications for developing our understanding of social organization at the earliest known settled village in coastal Oaxaca.

Obsidian Dome is a 550-650 year old, 1.5 by 1.8 km extrusion of high silica rhyolite situated along the Inyo Craters in eastern California. Field, and observations of drill core, reveals discrete metre-scale thick zones of rhyolitic glass exposed along the margin of Obsidian Dome as well as within its interior. Millimetre-scale flow-banded obsidian, pumice and rhyolite range from planar to chaotically folded, the latter a product of ductile, compressive deformation. Fractures, some of which display en-echelon splitting patterns are a result of brittle failure. Taken together, these features along with others, result from flow during lava dome growth and suggest complex emplacement patterns signified by vesiculation, crystallization and repeated brittle-ductile deformation, owing to episodic crossing of the glass transition. Evidence further shows that gas loss from the system occurred due to explosions, pumice formation and also brecciation of the melt as it episodically crossed the glass transition. Loss of gas by these mechanisms along with the inherent high viscosity of rhyolite melt explains the large amount of glass found on and within Obsidian Dome and other similar rhyolite extrusions in comparison to less silica-rich systems.

From excavations of burial complexes of the Early Bronze Age Cyclades (c. 3000-2200 BC) we know that obsidian was just as important and as widely consumed in burial contexts as it was in contemporaneous household contexts; Early Bronze Age Cycladic tomb assemblages are dominated by beautiful obsidian blades produced through a unique knapping technique reserved for burial contexts (Carter 2007; Dickinson 1994). The lack of sourcing studies in the area is an unfortunate pitfall in Aegean archaeology, as understanding patterns of source selection provides us with precious insight into the complex social structures and behaviors that characterized these ancient communities. The research detailed in this thesis set out to accomplish these goals for obsidian assemblages from 11 Early Cycladic cemeteries. Structurally, these assemblages are dominated by pressure-flaked blades manufactured specifically for funerary consumption, but also include a small number of blade cores and some pieces of flaking debris. Contextually, the composition of the assemblages reflects the social significance of body modification amongst these islanders, with the blades themselves likely used for depilation, scarification, and tattooing, and the cores reemployed as pestles in the grinding of pigments, as evidenced by pigment residues located on the artifacts (Carter 1998). Two additional assemblages from settlements on Crete were analyzed, one from a Late Neolithic cave site and another from a Late Minoan settlement. These assemblages served both to provide additional regional and temporal context for the Early Cycladic findings and to advance obsidian sourcing efforts in the Aegean as a whole. In order to characterize the chemical profiles of these artifacts for sourcing purposes, this study employed portable X-ray fluorescence spectrometry, a non-destructive archaeometric method which allows for the time- and cost-effective mass-sampling of objects on-site. The results display clearly that the Early Cycladic artifacts are overwhelmingly made from Melian obsidian, and approximately 88% derive from the Sta Nychia source. How far-reaching this procurement bias is throughout the Early Bronze Age Aegean is currently difficult to say, though contemporary data from previous studies, as well as the results obtained from the two Cretan assemblages in this study, seem to show a similar pattern. Future research integrating regional traditions of obsidian source selection with previously defined regional distinctions in pressure-blade technology is necessary in order to begin to map communities of practice across the broader Aegean.

No description available.

Obsidian Dome is a 550-650 year old, 1.5 by 1.8 km extrusion of high silica rhyolite situated along the Inyo Craters in eastern California. Field, and observations of drill core, reveals discrete metre-scale thick zones of rhyolitic glass exposed along the margin of Obsidian Dome as well as within its interior. Millimetre-scale flow-banded obsidian, pumice and rhyolite range from planar to chaotically folded, the latter a product of ductile, compressive deformation. Fractures, some of which display en-echelon splitting patterns are a result of brittle failure. Taken together, these features along with others, result from flow during lava dome growth and suggest complex emplacement patterns signified by vesiculation, crystallization and repeated brittle-ductile deformation, owing to episodic crossing of the glass transition. Evidence further shows that gas loss from the system occurred due to explosions, pumice formation and also brecciation of the melt as it episodically crossed the glass transition. Loss of gas by these mechanisms along with the inherent high viscosity of rhyolite melt explains the large amount of glass found on and within Obsidian Dome and other similar rhyolite extrusions in comparison to less silica-rich systems.

Obsidian Dome is a 550-650 year old, 1.5 by 1.8 km extrusion of high silica rhyolite situated along the Inyo Craters in eastern California. Field, and observations of drill core, reveals discrete metre-scale thick zones of rhyolitic glass exposed along the margin of Obsidian Dome as well as within its interior. Millimetre-scale flow-banded obsidian, pumice and rhyolite range from planar to chaotically folded, the latter a product of ductile, compressive deformation. Fractures, some of which display en-echelon splitting patterns are a result of brittle failure. Taken together, these features along with others, result from flow during lava dome growth and suggest complex emplacement patterns signified by vesiculation, crystallization and repeated brittle-ductile deformation, owing to episodic crossing of the glass transition. Evidence further shows that gas loss from the system occurred due to explosions, pumice formation and also brecciation of the melt as it episodically crossed the glass transition. Loss of gas by these mechanisms along with the inherent high viscosity of rhyolite melt explains the large amount of glass found on and within Obsidian Dome and other similar rhyolite extrusions in comparison to less silica-rich systems.