After the Sui and Tang Dynasties, the official seal gradually became larger, mostly Jiuding. After Wu Zetian came to power, she died of the evil "seal" sound and ordered to turn the seal into treasure. After Xuanzong of the Tang Dynasty, "Bao", as the special name of the emperor's seal, continued until the Qing Dynasty.
In addition, there are some nicknames for seals, such as Ji, Zhu Ji and Qi in Song Dynasty, pawn in Yuan Dynasty, Fu, Qi and Xin in Ming Dynasty. After the Qing dynasty, it was gradually eliminated, and only the seal script and seal continued to this day.
As a symbol, the characteristics of seals have remained basically unchanged since ancient times, but the frequent appearance of leisure stamps after the Tang and Song Dynasties can show that seals have gradually changed to artistic appreciation.
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