Material study of green stone artifacts from a Teotihuacan complex

Despite being one of the largest complexes at Teotihuacan, Plaza de las Columnas has been one of the least studied. Recent archaeological discoveries by the Project Plaza de las Columnas Complex revealed that its inhabitants maintained an evident relationship with the Mayan area. The methodology employed consisted first of a surface examination of the materials via imaging techniques. Afterward, mineralogical characterization was achieved via Infrared (FTIR) and Raman spectroscopies, and X-ray diffraction (XRD) for complementary analysis, while the elemental composition was evaluated by X-ray fluorescence spectroscopy (XRF) and scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). Results indicate a predominance of objects composed of quartz mixed with carbonates, with a minor number of objects identified as jadeite, albite, omphacite and serpentine. The methodology successfully characterized most of the archaeological objects and establishes new hypotheses regarding the degree of interregional interaction of the inhabitants of Plaza de las Columnas and the degree of access to raw materials and pieces from the Maya area.