Pyrite tesserae mosaics from El Caño (750–1100 CE), Panamá: Evidence of interactions between the Coclé and Maya regions

The study aims to identify the origin of mosaic stone tesserae mirrors discovered in El Caño, an archaeological site located in the Isthmus of Panamá within the archaeological tradition of Gran Coclé (750–1100 c.e.). The research objectives include (i) typological classification of the mirrors from El Caño by measuring the degree of similarity using the Jaccard coefficient, (ii) characterization of the materials used to make their stone bases, involving analyses such as optical microscopy, thin sections (petrography), Energy Dispersive Spectroscopy (EDS), X-ray diffraction (XRD); and (iii) identification of the tools used in their manufacture, through observations of marks using optical microscope and electron microscopy (SEM and Back Scattered Electron Detector [BSE]). The results indicate that (i) the mirrors found in El Caño are typologically similar to Maya mirrors from the Late Classic and Postclassic periods, (ii) the rocks used to manufacture the mirror bases are quartzose sandstone not observed in the geological formations in the Isthmus, and (iii) the tools used for shaping were limestone abrasives, consistent with the abrasives used by the Maya for shaping the stone bases of their mirrors. Considering these results, it is inferred that the artisans who manufactured the mirrors found in El Caño were Maya.