Q: I have a porcelain dinner plate with a hand-painted floral pattern and a mark with lettering so highly stylized it is nearly illegible. Can you tell me who made this plate and how old it might be?

A: If you look closely at the mark, you can see the word "Luneville" in stylized letters written over the letters "K" and "G" lying on their sides. This mark was used by Keller & Guerin from about 1880 to 1920. The pottery was established in Luneville, France, in about 1723 and operated under various owners. It was bought by Sebastian Keller and Jean-Alexandre Cuny in 1786. After Cuny left and Keller died, Keller's son-in-law, Charles Guerin, and Auguste Keller operated the business. The Keller family remained in the business until the early 1920s, when new owners took over and the name was changed to Societe Anonyme de Faienceries de Luneville, Badonviller et Saint-Clement (Earthenware Factory Luneville, Badonviller & Saint Clemente Ltd.). But pieces marked with the initials "K & G" (in various designs) continued to be made.