Three styles of cloisonné are most often seen: concave, convex, and flat. The finishing method determines this final appearance.Matthews, 146-147 With concave cloisonné the cloisons are not completely filled. Capillary action causes the enamel surface to curve up against the cloisonné wire when the enamel is molten, producing a concave appearance. Convex cloissoné is produced by overfilling each cloison, at the last firing. This gives each color area the appearance of slightly rounded mounds. Flat cloisonné is the most common. After all the cloisons are filled the enamel is ground down to a smooth surface with lapidary equipment, using the same techniques as are used for polishing cabochon stones. The top of the cloisonné wire is polished so it is flush with the enamel and has a bright lustre. Some cloisonné wire is electroplated with a thin film of gold, which will not tarnish as silver does.
