Over glazed marks

[Stan]

I would like to know when they started using over glazed reign marks, I know that over glazed marks were used in the Guangxu period and later, but were they used before? I am seeing a lot of Qianlong marks over glazed writen not in the Zhuanshu script, were all the imperial marks Zhauanshu script until Guangxi period?

[peterp]

In the Qianlong period the kaiti style marks were used, but they are so few that they are negligible. I have never seen a M&P item with that type of mark myself on an item, only in a Chinese mark book. Many collectors just consider them non-existent. The large majority are underglaze blue marks, no matter official or private kilns. Red marks are also few. Red marks did not take off until the Xianfeng or Tongzhi reigns.
Thus, my recommendation is to just assume the one below is from the late Qing or a later period.
As always, age needs to be estimated by the item itself not the mark. There are no shortcuts.