Analyses revealed the incense was made of a copal, a tree sap whose smoke the Maya believed nourished the gods.
The pigment was the famed Maya blue, and the flecks were bits of a white clay mineral called palygorskite.
According to previous studies, Maya blue is made by fusing palygorskite with pigments from the leaves of the indigo plant.
But the two ingredients do not readily combine, and it was unknown how the Maya fused them.
Archaeologists had suspected that copal was important to the production of Maya blue, and the new findings seem to confirm that theory.
"Our study suggests that heat and copal incense likely were key elements used to fuse the two components together," Feinman said.
Taken together, the bowl's history and its contents support the idea that Maya blue had great symbolic significance, study leader Arnold said.
Indigo, palygorskite, and copal—all associated with healing—were used individually as medicines by the ancient Maya.
"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.
The pigment's importance to the Maya is perhaps best illustrated by a 14-foot (4-meter) layer of blue silt that was discovered at the bottom of the Sacred Cenote when it was first excavated in 1904, the researchers say.
At the time archaeologists did not know what the blue material was, but the new findings strongly suggest it was Maya blue precipitate that had washed off of pottery and human bodies cast into the sinkhole.
Mary Miller, an art historian at Yale University in Connecticut who was not involved in the study, called the new findings "an exciting addition to the corpus of what is known about this stunning and tenacious pigment."
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