Forgive me-- I know there are a lot of Le Creuset problem posts on this site, but I couldn't find any with my same problem. Anyway, I think I may have taken off the black enamel from my LC skillet. I made a fritatta the other day on the stove top, then put it in the oven to finish it. I probably didn't use enough fat. When I washed it, there was this rusted-looking, bright orange circle, clearly where the flame was. I tried Bar Keepers friend and soap and water, but it's not coming off. I can't tell if it's on top of the enamel, or if the enamel is gone? Any advice on cleaning this thing? And is it safe to still use?