Bowl with six blue lines and perforations; Bowl of quartz fritware decorated in underglaze blue with blue stripes; a band with incised vines and small perforations over which a transparent slightly greenish alkaline glaze has been applied.; anonymous; Iran; c. 1175 - c. 1224; earthenware; cobalt (mineral); glaze; vitrification; h 7.9 cm d 19.2 cm d 7.6 cm