Strange blood stains on the 1,000-year-old gold mask

The ancient mask placed on the skull uses human blood, contributing to expressing the tomb owner's wish for rebirth.

Researchers working on the Sicán archaeological project discovered a golden mask in the 1990s while excavating an ancient Peruvian tomb. The tomb, dating to about 1000, belongs to an upper middle-aged man from the Sicán civilization who lived on the northern coast of Peru from the 9th to 14th centuries. The skeleton is painted bright red without a skull. and placed in a prone position in the middle of a square tomb 12m deep.

The golden mask in the millennial tomb. (Photo: Proteome Research)

The skull lies separate from the skeleton erected and wearing a mask painted red. Inside the tomb, the archaeological team found 1.1 tons of burial items and the remains of four other people including two young women in the position of a midwife and a pregnant woman with two children crawling. at a higher level.

At the time of excavation, scientists identified the red streak on the mask as cinnabar , a bright red mineral composed of mercury and sulfur. Although buried in the deep soil for 1,000 years, the red streak of 1-2 mm thick still clings to the mask.

In a new study published in the journal Proteome Research of the American Chemical Society, chemist Elisabeth Pires of the University of Oxford and her colleagues analyzed samples taken from red streaks to find out the secret ingredient that makes red streaks stick. into the mask. First, through infrared spectroscopy, which uses infrared rays to identify the composition of the material, the team found that the red streak contains proteins. They then used mass spectrometry, a method that helps classify different ions in a material based on their charge and mass, to find specific proteins.

The red streak contains 6 proteins found in human blood and proteins derived from egg whites. The proteins have largely decomposed, so it is not clear which bird's egg it is. But the team hypothesized it could be Muscovy duck eggs (Cairina moschata).

The cinnabar was often used by the upper classes and had significant ceremonial significance. The ancient people of the commoner class used a paint from ocher to paint objects.

Previously, archaeologists thought that the arrangement of the skeletons represented the desire for "rebirth" of the deceased patriarch Sicán. In order for the rebirth to take place, the ancient people covered the entire skeleton with blood-based paint, symbolizing bright red blood or "life force". Recent analysis found that the Sicán civilization sacrificed humans by cutting the neck and chest to maximize blood flow. Therefore, from an archaeological point of view, the custom of using human blood in paint is not surprising.