Centuries-old Maya Blue mystery finally solved

The new research shows that at Chichén Itzá the creation of Maya Blue was actually a part of the performance of rituals that took place alongside the Sacred Cenote. Specifically, the indigo and palygorskite were fused together with heat by burning a mixture of copal incense, palygorskite and probably the leaves of the indigo plant. Then the sacrifices were painted blue and thrown into the Sacred Cenote.

“These sacrifices were aimed at placating the rain god Chaak,” said Dean E. Arnold, Professor of Anthropology at Wheaton College, Research Associate at The Field Museum and lead author of the study. “The ritual combination of these three materials, each of which was used for healing, had great symbolic value and ritualistic significance.

“The Maya used indigo, copal incense and palygorskite for medicinal purposes,” Arnold continued. “So, what we have here are three healing elements that were combined with fire during the ritual at the edge of the Sacred Cenote. The result created Maya Blue, symbolic of the healing power of water in an agricultural community.”

Rain was critical to the ancient Maya of northern Yucatan. From January through mid-May there is little rain – so little that the dry season could be described as a seasonal drought. “The offering of three healing elements thus fed Chaak and symbolically brought him into the ritual in the form a bright blue color that hopefully would bring rainfall and allow the corn to grow again,” Arnold said.

Museum collections play key role

One of the keys to solving the mystery of Maya Blue production was a three-footed pottery bowl (Field Museum catalog number 1969.189262; see below for reference to image) containing rarely preserved copal dredged from the Sacred Cenote at Chichén Itzá in 1904 and traded to The Field Museum in the 1930s. Preserved in the copal were fragments of a white substance and blue pigment. Using The Field Museum’s scanning electron microscope, the authors studied these inclusions and found signatures for palygorskite and indigo. From this they concluded that the Maya produced Maya Blue as part of their sacrificial ceremonies.

“This study documents the analytical value of museum collections for resolving long-standing research questions,” said Gary Feinman, Curator of Anthropology at The Field Museum and co-author of the study.

But other knowledge was necessary to understand the significance of the bowl and the hardened copal it contains.

“This study required documentary, ethnographic and experimental research to establish the full context and use of the artifacts,” Feinman said. “Our work emphasizes the potential rewards of scientific work on old museum collections. It also shows that scientific analysis is necessary but not sufficient for understanding museum objects.”