Fig. 4From: Silver paints in medieval manuscripts: a first molecular survey into their degradation(left) SEM and (top right) microscope images of the microsample from the blue acanthus leaf (bottom right). Schematic depiction of its stratigraphy: layer 1 (gypsum ground); layer 2: calcium carbonate as filler (2a) is admixed with azurite (2b) for the blue colour; layer 3 brazilwood lake outline; layer 4 silver leafBack to article page