"Yier Zisun" jade seal of Hongwen Huigu collection, Ming-Qing dynasty, 16th-18th century; 2.1x2.2x2.6cm. © National Palace Museum, Taipei.

Emperor Qianlong tried to collect Eighty ancient seals, naming them "Hongwenhui Valley" and storing them in a box with four drawers. This seal is one of them.