that contain the reign name of Chinese emperors or a dynasty (reign marks) may sometimes hint to the period of production,
but this is actually quite unreliable due to the frequent use of non-period
marks, that is marks of an earlier reign or period in which an item was
It is known that some marks of the early Ming dynasty can be found on porcelain made later in the Ming dynasty. Even porcelain of the early Qing dynasty frequently shows reign marks bearing the name of Ming emperors. In the late Qing dynasty and republican era the reign marks of earlier Qing periods often were added with the intention to increase the perceived value of the porcelain.
An overall judgement of the porcelain piece is always necessary to verify if its real age and period mark fit together.
In the table below the reign name is listed and the duration is shown in western years. In reality, with imperial year notation the year count started again with year 'one', each time a new emperor was enthroned.
comparing the Chinese characters used in the marks of ceramics, the
emperors' reign names for the Ming and Qing dynasties are given in
Chinese on the following page:
Chinese emperors' reign names (in Chinese)
Please note that the imperial year notation which uses the reign name of the emperor in combination with the year during which something happened, was the most common way of recording events, history, etc. in ancient China.
This was not limited to ceramics and their marks.