I wouldn't take the chance. I have a coffee mug with a gold rim. I know it is not gold since it was a free mug from a grand opening at some store. When I tried to put it in the microwave the sparks started to fly. If you decide to try it, you should put a bowl with some water in it. You shouldn't put something dry in the oven without some sort of liquid. I read that somewhere sometime ago.
Sue