The Imperial date mark is usually written in six characters beginning with the name of the dynasty and ending with the words nien chih (made in the period): the nien hao coming in the middle:—
1 2 3 4 5 6
e.g. Ta ming ch´êng hua nien chih = made (chih)
4
in the Ch´êng Hua period (nien) of the great Ming (dynasty).
Occasionally the word nien is replaced by yü
(Imperial), yü chih meaning made by Imperial command; and in place of chih we sometimes find the word tsao
or more rarely tso