Secrets of 'Maya Blue' pigment probed

  |   April 2, 2013 at 5:04 PM
VALENCIA, Spain, April 2 (UPI) -- Spanish researchers say they've discovered how ancient Mesoamerican peoples made "Maya Blue," a durable pigment used for centuries on paintings and pottery.

Palace walls, sculptures and pieces of pottery produced by the ancient Maya incorporate the enigmatic Maya Blue, and although scientists have known the ingredients are a plant dye, indigo, and a type of clay known as palygorskite, the recipe of how they were "cooked" and combined has been a mystery.

This pigment, also used by other Mesoamerican cultures, has proven highly resistant to chemical and biological deterioration and centuries-old samples appear virtually unchanged.

Researchers from the University of Valencia and the Polytechnic University of Valencia report their analysis of Maya Blue has turned up an unexpected third ingredient.


"Indigo is blue and dehydroindigo is yellow," he said, "therefore the presence of both pigments in variable proportions would justify the more or less greenish tone of Maya Blue.


The researchers said they were investigating the secret of the unknown chemical bonds that bind the organic to the inorganic component and are the reason behind Maya Blue's centuries-long permanence.
