Wucai hexagonal jars of this type appear to be quite rare. A similar jar, also with Wanli mark, is in the National Palace Museum, Taipei, and illustrated in Enamelled Ware of the Ming Dynasty, Book III, Hong Kong, 1989, pls. 6-6c. Other similarly decorated hexagonal jars, with lobed sides rather than flat facets, bearing a Wanli mark, are in the Qing Court Collection, illustrated in The Complete Collection of Treasures of the Palace Museum - 38 - Porcelains in Polychrome and Contrasting Colours, Hong Kong, 1999, p. 35, no. 32; and in the Art Institute of Chicago, illustrated in Ming-Ch'ing, Chicago, 1964.