My sink has black on it inside. It is a white sink
Hi Robbie. I like to use Bar Keepers Friend on my white sink. It works well and removes the stains.
To me, it sounds like it needs to be re-done with new porcelain. They can make old tubs look like new. So I bet there’s someone who can redo your sink.
what kind of materials is it made from? Porcelain over cast iron? Acrylic?
If Barkeepers Friend doesn’t work, let us know and we’ll figure out what the source is.