Pottery & Porcelain Marks – Bowl & Urn: Simple designs of bowls, circles with a neck and topped with a line, were used in the 19th century when these marks first appeared. They were also used during the early 1920s on art pottery. Very elaborate urns and vases were marks in the early 1900s and continue to be used today. Factories in the United States and England were the main users of these marks, but those in Germany and Czechoslovakia also used them. Miscellaneous