I bought a pair of quarter sheet pans in the summer, and one of them has developed an odd problem. It has a grayish black coating that seems sort of like graphite was rubbed over the pan. It will come off on your hands, but at the same time, I cannot rub or scrub it off completely. It seems to be getting worse as time goes on—to the point I’m ready to throw it out. It also seems to be worse after I run it through the dishwasher, but the other one is not affected in the same way. It says they are dishwasher safe. I pretty much always cover them with foil when I use them anyway, and I can’t think of anything strange that I would have baked on them to cause this.
Does anyone have any idea what this is or has anyone experienced something similar?