Archeological excavations of the Templo Major project in Mexico city have brought to light a large collection of shell objects, several of them pearly. In many cases these mother-of-pearl objects represent attributes of certain deities: the epocololli or earmuffs, are distinctive for Ehécatl-Quetzalcoatl, the anáhuatl pectorals, characteristic of Tezcatlipoca, and the xopilcózcatl earrings adorn the ears of the gods of music and dance. "The purpose of this text is to show the studies that have been carried out on these conspicuous groupings with pieces of pearly shells, whose name in Nahuatl is epnepaniuhqui.ʺ (HKB Translation)--Page 4.