I can't answer your question, but I have thought some of these might be bsr. I have one. Mine is much worse than yours. The casting is missing part of the ring, with a lot of voids. It almost seems like these were made as seconds, or cheaply made as giveaways. My guess, without any real knowledge, is that they were made by whoever could provide the cheapest product at time. I'll see if I can find mine,and post a picture. I live near Atlanta, and the restaurant is still open, although I have never been there.