I purchased the large Symmetry set and several additional pieces. The inside coating has come off on top of the circles. I sent pictures and ask for replacement. The company says it is natural and nothing to worry about. I am very disappointed and DO NOT PLAN TO EVER BUY CIRCULON  BRAND AGAIN!!! THIS HAPPEN TO ONLY 3 of my pieces. I don’t  see how it is NORMAL!!   What good is a warranty.