Hidden behind the mask: An authentication study on the Aztec mask of the Museum of Ethnography, Budapest, Hungary.

Turquoise covered mosaic objects - especially masks - were attractive components of treasures transported to Europe from Mexico after the fall of the Aztec Empire in the 1500s. According to our present knowledge, the mosaic masks were manufactured for ritual purpose. The main material of mosaics, the turquoise was a high-prestige semi-precious stone among Mexican native people. During the 20 century, such objects derived both from illegal treasure hunting and documented archaeological excavations. The aim of our research was the authentication of a turquoise covered Aztec wooden mask, which presumably originates from the Tehuacán Valley, Mexico and exchanged by the Museum of Ethnography, Budapest, in 1973. The detailed and complex analytical investigation of the mask is a curiosity. To reveal the origin of the object, UV photographs were taken, the wooden base was subjected to biological studies and C-14 dating, the organic glue fixing the tesserae and the inorganic mosaic tesserae were investigated by non-destructive chemical, FT-IR and Raman spectroscopic methods. Our investigations determined that the mask of the Museum of Ethnography was made of an alder species of tree and its age is AD 1492-1653. The light-coloured covering mosaic lamellae were identified as alabaster and claystone. Comparing the turquoise tesserae cover with reference materials, their chemical composition has been clearly differentiated from most of the well-known turquoise sources of the US Southwest. Based on our results, the Aztec mask of the Museum of Ethnography proved to be an original piece of art from the 15th-17th century.