Archaeologists discover that the Sican civilisation, pre-dating Incas in ancient Peru, have used human blood as binding agent in a gold mask coloured with cinnabar, a red pigment.
According to the American Chemical Society (ACS) News service, thirty years ago “archaeologists excavated the tomb of an elite 40-50-year-old man from the Sican culture of Peru, a society that predated the Incas.”
The skeleton of the man was in a seated, upside-down position, and it was painted bright red, “as was the gold mask covering his detached skull.”
According to IFL Science, “the man’s detached skull, which unlike the rest of him, was right-way-up. An analysis of the chemical composition of the paint has been published in the American Chemical Society’s Journal of Proteome Research.”
The gold mask’s paint contained cinnabar, a toxic red pigment used in decorating the graves of people of high birth, a mineral made of mercury and sulfur. Up until now, it was unclear how the pigment had survived so long –– 1000 years –– being attached to the gold mask in a layer of 1 to 2 millimetres. “The identity of the binding material, that had been so effective in the red paint, remained a mystery,” the authors write.
Researchers reporting in ACS’ Journal of Proteome Research have analysed the paint, finding that, in addition to the red pigment, it contains human blood and bird egg proteins.
“Blood proteins appeared in the first search against all natural proteins, which led to a search against the blood database, which yielded a match against chimpanzee (Pan troglodytes),” says Luciana Carvalho, an archaeologist at the University of Oxford specialising in organic residues on metal objects, in an email to
Gizmodo. “As chimps are not found in Peru, we conducted a search against human blood protein database, which provided perfect matches.”
ACS noted that the scientists discovered proteins in on the masks, and later identified six of them as human origin. Other proteins came from egg whites, but the scientists weren’t able to pinpoint which bird because the proteins were highly degraded. However, they assume it is the Muscovy duck.
“Inside the tomb, archaeologists discovered 1.1 metric tons of grave goods and the skeletons of four others: two young women arranged into positions of a midwife and a woman giving birth, and two crouching children arranged at a higher level,” Live Science
The ACS news release suggests that the identification of human blood proteins “supports the hypothesis that the arrangement of the skeletons was related to a desired ‘rebirth’ of the deceased Sican leader, with the blood-containing paint that coated the man’s skeleton and face mask potentially symbolising his ‘life force,’ the researchers say.”
IFL Science reports that the Sican culture lasted for “at least 500 years.” The tomb from the Middle Sican Period (1,100-900 years ago) apparently survived “undisturbed beneath the Huaca Loro temple” until the 1990s, while similar elite graves were looted by grave robbers.
According to IFL Science, “It was the first elite Sican tomb from the Middle Period to be scientifically excavated.”
As for the Sican culture, it was one of the major pre-Incan civilisations of modern Peru: “Seven hundred years have wiped away most knowledge of the Sicans, but the elaborate gold objects retrieved from tombs tell us much of what we do know.” For example, the chemical analysis of the paint on a gold mask “turns out to contain human blood and bird egg proteins.”
The news release notes that “the Sican was a prominent culture that existed from the ninth to 14th centuries along the northern coast of modern Peru. During the Middle Sican Period (about 900–1,100 A.D.), metallurgists produced a dazzling array of gold objects, many of which were buried in tombs of the elite class.”
The tomb in which the skeletons and the mask were found was first excavated in the early 1990s by “a team of archaeologists and conservators led by Izumi Shimada.”
“At the time, scientists identified the red pigment in the paint as cinnabar, but Luciana de Costa Carvalho, James McCullagh and colleagues wondered what the Sican people had used in the paint mix as a binding material, which had kept the paint layer attached to the metal surface of the mask for 1,000 years.” As it turns out, the Sicans used human blood and egg whites as binding material in the paint mix.
THUMBNAIL PHOTO: The Metropolitan Museum of Art in New York, NY, has a similar funerary mask from 9th-11th century Peru; (Lambayeque) Hammered gold with cinnabar and copper overlays, cinnabar; H. 29.2 cm (Wikimedia Commons/Rosemania)
HEADLINE PHOTO: The 1,000 year-old Sican death mask likely adorned the skull of an elite person and was dyed with cinnabar and human blood. (Izumi Shimada)
Source: TRT World