It is possible that the hallmark belongs to Zhang Yufan who was active during the 1930s. Although no published information exists on Zhang, the hallmark style compares well to marks appearing on two vases of the same period, the first bearing a Yonghuatang Zhi hallmark and signed by Liu Xiren; and the other with a Hongxian mark and bearing the signature of Wang Dachang. Both vases are published by S. Kwan, Brush and Clay, Chinese Porcelain of the Early 20th Century, Hong Kong, 1990, nos. 111 and 112.