Discovery of indigoid-containing clay pellets from La Blanca: significance with regard to the preparation and use of Maya Blue

Analytical studies using extraction/liquid chromatography, pyrolysis-silylation gas chromatography-mass spectrometry, visible and infrared spectroscopies, solid state voltammetry and electron microscopy on a set of spherical greenish pellets discovered in the Structure 4H1 of the ancient Maya site of La Blanca (Peten Department, Guatemala), dated in the Terminal Classic period, confirm the presence of indigoids (dehydroindigo, indigo) associated to palygorskite. The appearance of such pieces, whose origin and function is uncertain, but most likely correspond to residuals of a decorative plaster, can be considered as indicative of the use of Maya Blue in a quotidian context, thus suggesting that the materials used for Maya Blue preparation where used not only in ritual contexts. This would be consistent with the idea that the Mayas could make a versatile use of such materials and that their symbolic value could vary with time during the evolution of Maya culture. (C) 2013 Elsevier Ltd. All rights reserved.