Sơn mài — "polish-grind lacquer" — is the Vietnamese fine-art lacquer painting tradition that fused ancient Asian lacquer craft with French oil-painting principles in 1920s Hanoi. Painters built up ten to thirty layers of sap-lacquer ground on wooden panels, inlaid crushed eggshell, gold-leaf, silver-leaf, mother-of-pearl, and cinnabar, then polished the surface back with charcoal-water to reveal stratified luminosity beneath glass-smooth depth.

The visual canon says: deep red-black "cánh gián" ground, gold-leaf moon and clouds, eggshell-mosaic figures, mother-of-pearl water-glints, cinnabar accents. The result glows from within — twenty layers polished smooth as a mirror, ornate ancestral craft framed by modernist composition.