Removing Rust From Porcelain or Ceramic Porcelain dishes, porcelain fixtures and ceramic tiles are more fragile than cement. Rub the stain with borax or lemon juice. For tougher stains, you can use a wet pumice stone, but be careful because it can scratch a surface. Allow the area to dry and then rinse with clean water. If the stain persists, repeat the procedure. Once the rust is removed, make sure to thoroughly dry the area. Barnwood Tables
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Fels Naptha is the best stain treatment and it is cheap. Check out this post on how it gets almost anything out!
stain removers...I cant wait to try some of the others. The shower cleaner is miraculous for removing soap scum without harsh chemicals, which incidentally dont work as well anyway!
How to Remove Stains from Laundry Download and print this handy chart showing how to remove common varieties of stains. Post a copy in your laundry room for quick reference. (From Better Homes and Gardens)