An Experiment: Will Toothpaste and Baking Soda Remove Rust Stains

Recently I read in Better Homes and Gardens that you can remove rust stains from porcelain with toothpaste and baking soda.  My porcelain bathtub had several rust spots from a shaving can that had rusted.  I tried may different ways to remove the rust spots but nothing has removed them. So I decided that I…