Fig. 3From: Formation mechanism of copper-gilded coronet ornaments excavated from a Sui or early Tang tomb situated in Xi’an, Shaanxia Flat surface and scratch of TB; b Granular morphology of the gold layer of TB; c Cross-sectional BSE-SEM image of TB; d Polishing traces on the surface of SD; and e Granular morphology of the gold layer of SDBack to article page