Fig. 7From: Characterizing the sealing materials of the merchant ship Nanhai I of the Southern Song DynastyMicrographs of a cross-section of sample A’s black and white layers under SEM, b cross-section of sample A’s black and white layers under optical microscope, c cross-section of sample A’s grey layer, d pyrite crystals on the surface of sample A, e rod-shape calcite on the surface of sample A, and f cross-section of sample B layers under SEMBack to article page