Reports this week announced that researchers have ‘solved the mystery’ of how Maya Blue was made (National Geographic News, New York Times), off the back of a paper published in the journal Antiquity. The vivid pigment, which was painted on human and other sacrifices, has been a focus of interest for decades. Although the main ingredients of the pigment – indigo and clay – have long been known (see this 1966 paper in Science), archaeologists have wondered about the details of how, when and where it was made.
The paper describes the study of a particular pot of incense in which researchers discovered flecks of clay and indigo. The slow-burning incense resin provided the heat needed to create the paint, and, according to LiveScience, might have been a key ingredient in binding the other ingredients together. The bowl was then chucked into a sinkhole thought to be a portal to the spirit world. The location and the incense suggest that “the production of the ancient Maya blue was based on the performance of the religious rituals” (The Chicago Tribune). Although the find may not be too surprising, the bowl appears to be the first artefact to show evidence of the pigment production process.
The recipe behind Maya Blue also made news in 2002 (National Geographic). That team patented a number of ‘Maya Blue’ recipes in 2006, including one that involved a combination of indigo, clay, and resin.