Multispectral Imaging and Spectral Classification of Naj Tunich Pigments

摘要

Archaeologists frequently discover artifacts that contain a great deal more information than can be detected with the human eye. This is particularly true of contexts with inscriptions or paintings. Painted texts in Maya caves are among the rarest of these contexts with only five sites currently known. Naj Tunich is preeminent among these as its corpus of inscriptions exceeds that of the other four combined. Because caves were considered sacred features in the ancient Maya landscape, cave inscriptions may deal with esoteric beliefs and fundamental tenets of Maya religion that are not recorded elsewhere. The decipherment of these texts may, therefore, provide important insights into Maya culture. Visible and near-infrared multispectral images of the Naj Tunich inscriptions have been obtained. Selected images have been analyzed and differences in the spectral reflectance of the pigments noted. Spectral signatures were used to classify pigments and suggest that markedly different pigment compositions were used at Naj Tunich. At least three different pigments have been shown to be in use. Several drawings contain more than one pigment and show evidence of touch-up or over-painting. Pigment compositional differences have been used to reevaluate proposed artistic relations between drawings. Spectral classification has isolated unsuspected temporal and artistic complexity in the Naj Tunich inscriptions which have led to increased archaeological understanding of the production and significance of these works. Spectral classification results and implications for the Naj Tunich corpus are presented.