Material Composition and Manufacturing Techniques of Western Han Lacquer Pots: A Scientific Analysis of Two Excavated Vessels from Wulong, Chongqing

Lacquerware craftsmanship of the Western Han period is well known, yet the specific material choices and formulation techniques remain poorly understood. This study investigates two lacquer pots (dated to 186 BCE) from the Guankou cemetery in Chongqing, as a case study to explore their manufacturing characteristics. We characterised the artefacts using wood anatomical analysis, scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS), and pyrolysis–gas chromatography–mass spectrometry (Py-GC/MS), enabling systematic analysis of wood substrates, layer sequences and material compositions. The results reveal a functional tailoring of materials: the round pot was made of lightweight poplar, whereas the flattened pot used harder, dimensionally stable crape myrtle. Structurally, the round pot exhibits a four-layer sequence (wood core, clay–ash ground with aluminosilicate fillers, base lacquer, and cinnabar-pigmented decoration), while the flattened pot has a simplified two-layer construction with lacquer directly on wood. Both artefacts utilise natural lacquer from Toxicodendron vernicifluum, but the round pot employs a pure-lacquer system, whereas the flattened pot incorporates a blend of lacquer and drying oil. These findings, based on two vessels from a single tomb, demonstrate technological diversity and suggest customised formulation in early Western Han lacquer production. This work provides empirical case-study evidence for research on craft traditions, regional manufacturing characteristics, and the history of lacquer-related materials science.