Brise fans form one of the most important and popular types imported from China throughout the 18th and early 19th centuries. These fans were usually fashioned of carved and pierced ivory worked to a maximum degree of fineness. Produced strictly for export, they were shipped to England from Canton. Towards the end of the 18th century piercing often gave way to elaborate carving, generally covering the entire surface of the fan, which featured genre subjects sometimes referred to as "Scenes from Chinese Life." In some cases shield shapes were incorporated into the pierced or carved designs to hold the initials of European women. Some of ivory brise fans were large, but smaller versions also appeared. During the 19th century the innovation of double sided carving was introduced. This carving is identical on both sides of the fan. The finest brise fans were created during the decades from 1750 to 1830. Production continued after this date, but workmanship deteriorated.