Which traditional Chinese craft decorates objects with many layers of hardened tree resin?

The traditional Chinese craft that decorates objects with many layers of hardened tree resin is Chinese lacquerware.

Lacquerware is made by applying sap from lacquer trees to a prepared object, often made of wood, bamboo, or a lightweight composite core. The coating is allowed to cure, then additional layers are applied, sometimes followed by polishing, painting, carving, or inlay. Because the process can require many layers and considerable drying time, finely made objects may take months or longer to complete.

Chinese lacquer traditions include painted lacquer, carved lacquer, and techniques incorporating gold, mother-of-pearl, or other materials. The resin is not ordinary varnish: natural lacquer comes from Toxicodendron trees and can irritate skin before curing. Lacquerware is also distinct from cloisonné, whose decoration is made from fired glass enamel held in metal compartments.