"Studies of paint found in the pores of the stones confirmed that Mexica sculpture, as Greek and Roman, was polychrome. An interdisciplinary team coordinated by the National Institute of Anthropology and History (INAH), has determined the nature of pigments and agglutinants, pictorial techniques and symbolism of Mexica polychromy."
The investigation, announced by INAH Direction of Archaeological Studies, Leonardo Lopez Lujan, analyzed trace amount of pigments on scultpures from the National Museum of Anthropology and Templo Mayor Archaeological Zone and Site Museum to determine that the chromatic palette of the Mexica was made up of 5 colors: red, ochre, blue, white and black.
The Sun Stone is a good example: "It was cleaned and analyzed in 2000, as part of the remodeling of Mexica Hall, at MNA, celebrations. Although it was exposed to the elements almost a century, a group of INAH restorers directed by Mari Carmen Castro achieved to detect rests of red and ochre pigments in the stone pores."
"In 2007, the team leaded by archaeologist Fernando Carrizosa made the same observations at the lunar deity Coyolxauhqui monolith, finding evidence of red, ochre, blue, white and black paints. Other studies confirm it, concluding that Mexica palette was limited to these 5 colors; shades like brown or pink were never used in sculpture or mural painting."
Lopez Lujan informed studies made in 2008 and 2009 on the paint over Tlaltecuhtli monolith, found in October 2006 in Mexico City Historical Center, have deepened; "Soon after Tlaltecuhtli was exhumed by members of the Urban Archaeology Program, we took abundant samples of the pictorial layer, which had an excellent conservation state."
"These analyses determined raw material used by Mexica to elaborate pigments and agglutinants. We also identified pictorial techniques used by Tenochtitlan artists more than 500 years ago."
The INAH archaeologist explained that among previous attempts to reconstruct chromatically the Sun Stone and Coyolxauhqui, some specialists like Robert Sieck Flandes, in 1942, and Carmen Aguilera, in 1985, based their studies on codices images, achieving interesting results.
The results presented now, however, part from using analytical methods and technological resources, proving that the palette of Tenochtitlan sculpture is more reduced than that from codices; in the future, reconstructions will have to be done based on direct observation of monoliths.
Lopez Lujan remarked that Mexica sculptors used mainly volcanic stone as basalt, andesite and tezontle, which natural hues are blackish, grayish and pinkish.
"These are the colors that dominate in pieces exposed at museums. Most sculptures have lost most of the pictorial layer, due to action of soil elements when buried, and once exhumed, to the action of weathering".
Main results from investigations are to be published in Arqueologia Mexicana magazine and the books Monte Sagrado-Templo Mayor (Sacred Mount-Main Temple) written with Alfredo Lopez Austin, and Escultura monumental mexica (Monumental Mexica Sculpture), written with Eduardo Matos Moctezuma.
Thanks to Iona for the suggestion.