McCormick Student Helps Uncover Ancient Ritual

March 10, 2008

Maya blue. The color has fascinated and confounded scientists and anthropologists for decades. In the ancient Mayan civilization, the color adorned pottery and murals, and human victims were painted head to toe in the light blue hue before their beating hearts were cut from their bodies as a sacrifice to the rain god Chaak.

But researchers never knew exactly how the pigment was produced. Now, with the help of a McCormick undergraduate student, researchers think they’ve found the solution.

Jason Branden (materials science and engineering ’07) was taking both an electron microscopy class at McCormick and an archaeological methods laboratory class at the Field Museum in Spring 2006 when he first got involved with the project. Both classes required a project, and Branden was interested in applying engineering analysis methods to archaeological finds. A professor recommending working with Dean Arnold, an anthropologist at Wheaton College who had been studying Maya blue for years.

Arnold knew that materials scientists long ago discovered the components of Maya blue — indigo and the clay mineral palygorskite — but no one really knew exactly how the Maya people created the sacred pigment.

Arnold was perusing a list of artifacts at the Field Museum when he came across a bowl that had been dredged more than 100 years ago from the Sacred Cenote, a deep pool in a Maya complex in the Yucatan Peninsula where Mayans made offerings to the god Chaak.

Arnold suspected the bowl contained both indigo and palygorskite as well as copal incense — a material that could have been used to create the low-temperature heat needed to fuse the materials together.

That’s where Branden came in.

“My role was to identify the colored remnants in the copal mass to see if the blue was, in fact, indigo and the white was palygorskite,” he says. Branden used his new knowledge of scanning electron microscopy and energy dispersive x-ray spectroscopy to identify the materials and validate Arnold’s hypothesis. Researchers then concluded that Mayans created the pigment in bowls like this one as a religious ritual at sacrificial sites.

“I thought it was a really interesting way to see how engineering methods are applied to non-traditional engineering projects,” Branden says. “I was interested in learning more about the significance of this dye in the culture, its importance to the archaeological and art worlds, and seeing how engineering could help influence these discoveries. There was a fusion of so many different ideas on so many levels.”

Since the research paper was published in the journal Antiquity, media outlets like the Chicago Tribune and the New York Times have covered the finding.

“It’s causing quite a stir in the archaeological world,” says Branden, who now works for Cessna Aircraft. “I was just happy to assist Dean Arnold in this groundbreaking find.”

In addition to Arnold and Branden, other authors of the paper include Patrick Ryan William, Gary M. Feinman, and J. P. Brown, all of the Field Museum.

-- Emily Ayshford