Topic: Bing & Grondahl

[josordoni]

B&G and Royal Copenhagen have both made commemorative plates from the 19th century.

Jamiri is an excellent site for all things RC and B&G, including dating the marks, and the artists.

http://www.jamiri.dk/Royal-Copenhagen-12.htm

as is Cornelius Hansen - here you will find all the plates in date order with illustrations. 

http://www.cornelius-hansen.com/

[josordoni]

They can sell for as much as 50 euros, my wife bought a whole box load for 20 euros, there were 32 in the box

It's highly dependent on the date - the best ones to look for are those dated before 1920.  Also the 1940-60 can make reasonable money, but the latest ones are not easy to sell.