This is a vintage Abingdon art pottery shell shaped blue glazed large oval bowl or serving dish. Abingdon Pottery was located in Abingdon, Illinois, and only produced art pottery pieces between 1934-1950. This blue shell dish is 12" x 7 3/4." It is in excellent condition with no chips or cracks. It has a stamped ink "Abingdon USA" mark on the back that is partially covered by the blue glaze.