Kanin came to be stamped on papers after the age of the Tang Dynasty, but until the period of Wei and Jin in the Northern and Southern Dynasties, kanin were stamped on 'fudei' (a lump of clay) which was used to seal a bundle of mokkan or chikkan (narrow, long, and thin pieces of wood or bamboo strung together that were used to write on in ancient times).
なお、紙に押して使うようになったのは唐代以降で、魏晋南北朝時代までは木簡・竹簡の束を止める「封泥」という粘土の塊に押していた。