Traces of three-thousand-year-old silk found on Sanxingdui bronze masks

Silk on the masks from the sacrificial pits

Bronze masks from the sacrificial pits of the Sanxingdui archaeological complex in China's Sichuan province have preserved traces of silk about three thousand years old. This was reported by Gazeta.Ru citing a publication in the journal Antiquity. A team led by Guo Jianbo of the Sichuan Provincial Institute of Cultural Relics and Archaeology found remains of fabric on 101 objects, including 94 bronze items.

What exactly was discovered

On one of the large masks, three fragments of fabric survived near the right eyebrow and eye. Differences in weaving and preservation indicate that the mask was covered or decorated with several pieces of silk. Traces of fabric were also found on an animal-shaped mask. In two recently excavated pits, scraps of fabric lay beneath the objects, sometimes in several layers, suggesting the masks were deliberately placed.

Dating and context of the finds

The objects date to the late Shang period, around 1300–1046 BCE. Excavations at Sanxingdui began in 1986 and yielded more than 780 bronze objects, and from 2019 to 2022 archaeologists uncovered six more sacrificial pits. Many finds in them are broken or burned — in the researchers' view, the ritual objects were deliberately destroyed.

Technology and preservation

The surviving fragments differ in technique: from loose gauze fabric to dense silk with complex patterns. In thread density, some samples match or exceed the level of China's Central Plains of that time. Laboratory tests revealed traces of red ochre, calcite and, presumably, an organic red dye; in one case the paint had soaked into the fibers, but it has not yet been possible to establish the source of the pigment or determine whether the silk was dyed directly at Sanxingdui.

Why the fabric survived and what it means

The thin threads have survived to this day largely thanks to the corrosion of the bronze: copper, as it oxidized, helped preserve the fibers. Some samples were charred, while others retained their original structure. Microscopic and chemical tests confirmed that the material was indeed silk, not animal wool.

Ritual role and open questions

Silk, according to the researchers' conclusions, was part of Sanxingdui's ritual system alongside bronze, jade and ivory. The fabric may have served as a 'material medium' in religious ceremonies, helping to link earth and heaven — a role of silk known from later written evidence from other regions of China. The authors also suggest that writing or symbols may have been applied to the fabric: no systematic written sources have yet been found at Sanxingdui, and the hypothesis that messages were recorded on perishable material remains open.