This is a really sharp Schumann Arzberg Bisque Porcelain Bowl in an OP ART Style. Very Mid Century Modern. Is has a Design of Jagged Rock. In good vintage condition. No chips or cracks. The size is 2 1/8" high x 5 3/4" diameter. Hallmarked on the base. Great addition to a collection for contrast with German vases of similar styles. I have many unique items listed. Well priced and will combine shipping. Great gift ideas.