In a groundbreaking study published recently in the Proceedings of the National Academy of Sciences, researchers from Tulane University in collaboration with Mexico’s Proyecto Templo Mayor have unveiled new insights into how obsidian—a volcanic glass that was a cornerstone of pre-Columbian Mesoamerican technology and ritual life—moved across ancient landscapes and shaped the sociopolitical fabric of the Mexica (Aztec) Empire. By conducting the largest compositional analysis of obsidian artifacts ever recovered from the heart of Tenochtitlan, this research reveals a finer-grained picture of trade networks, craftsmanship, and imperial control that challenges earlier assumptions about economic integration and political influence in one of the Americas’ most iconic capitals.
The study systematically analyzed 788 obsidian fragments from the Templo Mayor, the sacred core of Mexica power situated in present-day Mexico City. Utilizing portable X-ray fluorescence (pXRF), a non-destructive analytical technique that accurately identifies the geochemical fingerprint of stone artifacts, the team was able to pinpoint the precise provenance of these materials. This cutting-edge methodological approach allowed researchers to traverse spatial and temporal boundaries, reconstructing complex supply chains and making visible the flow of goods that underpinned the Empire’s functioning.
Obsidian, prized not only for its sharp edges but also imbued with symbolic and ritual significance, was predominantly sourced from the Sierra de Pachuca region. This particular green-hued material held a mythological resonance, associated with Tollan—the legendary city-state revered in Mexica cosmology. The study found that nearly 90% of the obsidian artifacts, especially those linked to ceremonial contexts such as miniature weapons, decorative inlays, and jewelry, were crafted from this source, underscoring its centrality to religious and political authority.
Yet, the research uncovered a more nuanced picture of economic activity beyond the preferential use of Pachuca obsidian. Tools and utilitarian implements were made from obsidian procured at a minimum of seven other distinct geological sources, some lying well beyond the borders of Mexica control. Among these were regions like Ucareo in the Purépecha territory and Otumba and Tulancingo, indicating a widespread and diverse trade network. This evidence challenges prior narratives that framed Mexica dominance solely in terms of military conquest, highlighting instead a sophisticated market economy that facilitated the movement of valuable raw materials across rival polities.
The material culture unearthed at the Templo Mayor reveals patterns of both centralized state control and decentralized market trade. While ceremonial objects remained tightly controlled and meticulously standardized, as reflected in the exclusive use of Pachuca obsidian after the empire’s consolidation around 1430 CE, everyday tools demonstrate a broad availability of resources accessed through local markets. This duality mirrors a stratified society wherein ritual purity and political symbolism demanded strict regulation, but the general population engaged in a vibrant and competitive marketplace.
Notably, the temporal dimension incorporated in the study reveals shifts in obsidian use and distribution over nearly a century and a half—from the foundation of Tenochtitlan circa 1375 CE to its fall in 1520 CE. Early phases of the city’s growth exhibit a greater diversity of obsidian sources across both ritual and practical artifacts, indicative of a more pluralistic trade environment. As the Mexica state expanded and centralized power, a process of religious and economic standardization emerged, evident in the increasing dominance of Sierra de Pachuca obsidian in ritual contexts. This transition marks a tightening of control mechanisms that paralleled imperial ambitions and sociopolitical restructuring.
The analytical power of portable X-ray fluorescence played a pivotal role in deciphering the provenance and use of obsidian artifacts. This non-invasive technology offers real-time geochemical readings without damaging precious archaeological materials, enabling a largescale compositional study that would have been impractical with traditional destructive sampling methods. By mapping elemental compositions, the research draws direct lines between raw material sources and finished artifacts, painting an intricate portrait of ancient economic interconnectivity.
The collaboration between Tulane University and Mexico’s Proyecto Templo Mayor, affiliated with the National Institute of Anthropology and History (INAH), underscores the importance of cross-institutional partnerships in advancing our understanding of the past. Combining expertise in field archaeology, geochemical analysis, and anthropological theory, the team successfully reconstructs the multifaceted networks that sustained the Mexica capital and broadens our knowledge of Mesoamerican political economy.
These findings have broad implications for how archaeologists and historians interpret imperial economies in non-Western contexts. The Mexica Empire did not rely solely on brute conquest to extract resources; rather, it sustained complex trade relations with politically distinct groups, integrating goods into its markets and religious life. This insight compels a reevaluation of the mechanisms behind empire-building, emphasizing negotiation, alliance, and economic exchange alongside military dominance.
The research also contributes methodologically by showcasing how archaeometric approaches can be applied to large artifact assemblages to uncover patterns invisible to traditional archaeological techniques. This kind of scientific analysis enriches material culture studies, providing objective data to support or contest long-held cultural assumptions. It exemplifies how technological advancements in archaeology are transforming our capacity to explore ancient societies in unprecedented detail.
Beyond its scholarly impact, the study invites broader reflection on the symbolic power of obsidian in shaping identity and authority within the Mexica worldview. The elevated status accorded to green Pachuca obsidian in ritual artifacts underscores how material properties can acquire ideological weight, intertwining geology, mythology, and power. This multi-layered significance of natural resources extends our understanding of how premodern societies constructed social hierarchies and spiritual orders through their material environment.
In sum, the compositional analysis of obsidian artifacts from Templo Mayor not only enriches our knowledge of Mexica economic and political systems but also provides a vivid window into the dynamic and interconnected world of ancient Mesoamerica. It illuminates the myriad ways in which raw materials transcended physical and political boundaries, shaping not only the everyday lives of commoners but also the sacred rituals that affirmed imperial legitimacy. As archaeology integrates scientific innovation and interdisciplinary collaboration, studies such as this one redefine our appreciation for the complexity of pre-Columbian civilizations.
Subject of Research: Compositional and provenance analysis of obsidian artifacts from the Mexica (Aztec) Empire’s capital, Tenochtitlan, with implications for understanding economic networks, ritual practices, and political organization.
Article Title: Compositional analysis of obsidian artifacts from the Templo Mayor of Tenochtitlan, capital of the Mexica (Aztec) Empire
News Publication Date: 12-May-2025
Web References: DOI Link
Keywords: Archaeology, Cultural anthropology, Physical anthropology, Architecture, Prehistoric archaeology, Archaeological periods, Archaeological sites, Historical archaeology, Material culture, Sociopolitical systems, Applied anthropology, Economic anthropology, International trade, Economic history, Human geography, Urban studies
