Here is an interesting question, is old dinnerware radioactive ? Well the truth, YES, some old dinnerware is radioactive. It seems that prior to World War Two almost all American dinnerware used uranium oxide in their glazes. In fact the red glazed dinnerware contained a pretty good amount of uranium oxide. Did dinnerware manufactures wise up and stop using uranium oxide ? Well, for a while they did. Surprising to most people, they started the practice back up again, in 1959 mainly in the brightly colored dishes, for example Fiesta Ware. By the late 1980's the practice had ceased.  Will the Gamma rays hurt you ? I dont know, from what I understand the older Fiesta Red (prior 1944) emits the most Gamma rays. I would not want the stuff around me, personally. The raw uranium that leaches through the dishes through use, is probably more dangerous then the Gamma emissions . If your eating regularly off dinnerware, pre 1944, I would stop.

A very detailed analysis of the radiation exposures due to uranium in dinnerware can be found in the Nuclear Regulatory Commission publication “Systematic Radiological Assessment of Exemptions for Source and Byproduct Materials” (NUREG 1717).