Kangxi dishes with raised boss in center

Enclosed are a few photos of one of a pair of Chinese Export dishes that I got recently, dating to the Kangxi or the Yongzheng period. They both have a raised boss in the center.

What is the purpose of the raised center? Wine tasters have a similar center that helps in judging the color of the wine. Any ideas?

"Steamed bun center bowls"

From the style and date of these plates, we can assume that the intended market was the Dutch or possibly the Brittish market.

As for the shape, as far as I am concerned, these dishes will remain a mystery.

From similar dishes made of silver, the raised center seems to have been introduced just to help keeping the plates in shape. I recently saw plates with similar raised centers at the Singapore Historical Muesum, described as sacrificial plates.

It has also seemed likely that dishes of this kind was to be used under silver ewers with the raised center there to fit the base of the ewer and to help keeping it in place, but I have never seen any dishes like these with even the tiniest wear to indicate they have ever been used like that.

In another source, these plates was called "oyster plates".

The Curator Emeritus of the Asian Art Museum in San Francisco, Clarence Shangraw, tells that this type of bowl first appeared in the Xuande period of the Ming Dynasty and that the few survivors of this type mostly date to the transitional period. They are called "Man tou xian" bowls where Man tou means "steamed bun" and xian means "center". The raised boss in the center of these early plates was were there to serve as a seat for a steamed bun to sit on above the soup.

Further information - if someone possibly could have seen a Dutch painting with one of these plates on - would be highly appreciated.

Jan-Erik Nilsson