Maya blue -- a vivid, somewhat turquoise-colored pigment used for about a millennium by Mesoamerican peoples to decorate pottery, figurines and murals that has long mystified scientists.
The Maya blue pigment resists age, acid, weathering, biodegradation and modern chemical solvents. Previous research had identified two ingredients as extract from the leaves of the indigo plant and an unusual white clay mineral called palygorskite. Copal, a tree resin burned as incense, also was part of the Maya blue concoction.
Researchers did microscopic analysis on material found in a three-footed pottery bowl in the museum's collection dating from A.D. 1400 that had been used as an incense burner. A century ago, the bowl was dredged from the Sacred Cenote, a natural sinkhole well, at Chichen Itza, a key urban center late in Maya history
During the rituals conducted on the edge of the cenote at Chichen Itza, the Maya seem to have produced the pigment and painted items like pottery that would be tossed into the water as offerings to the god.
They also would paint people being offered as human sacrifices blue and heave them into the sinkhole. About 120 sets of human remains have been dredged from the sinkhole, along with lots of ceremonial objects.
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