Enamel
Enamel is an opaque glassy covering, white or colored, used on china or on metal objects, as protection, waterproofing and decoration. The use of enamel as embellishment to decorate jewelry originated among the Assyrians and was widely accepted among the Egyptians. The Byzantine works and those made in Limonges (France) in the Middle Ages are very refined, particularly the beautiful "cloisonnes enamels", sockets with prominent edges.