Revealing the lacquering materials and techniques in Northwest China during the Western Zhou period

Recently, a number of lacquerware were unearthed at the Yaoheyuan site, which was found as the Huo State during the Western Zhou period (1046–771 BCE). A comprehensive scientific analysis was conducted by multiple analytical techniques, including optical microscopy, scanning electron microscopy–energy dispersive X-ray spectrometry (SEM-EDS), Raman spectroscopy, X-ray diffraction (XRD), and pyrolysis–gas chromatography/mass spectrometry (Py-GC-MS), to investigate the materials and manufacturing techniques of these lacquered artifacts. Results show that a typical three-layer structure, comprising the ground layer, the lacquer layer and colored painting layer, was predominant at the time. Evidence of multiple lacquer or ground layers found in a few of lacquer film indicates that lacquerware-making techniques were progressively advancing. A variety of materials were identified in the manufacturing process, including urushiol-based lacquer, drying oil, animal glue, clay, cinnabar and malachite. Furthermore, the manufacturing origin of the lacquerware in the site was discussed.