I used to always associate bar keepers friends with stainless steel. But while dogsitting for a friend, I left a dogfood can overnight to soak in the sink, and I awoke the next morning to find myself with a stubborn rust stain. No amount of dish soap and scrubbing would budge it. I had heard comet is too abrasive (making the sink easier to stain in the future), but bar keeper’s friend seemed worth trying.
It worked like a charm! And not only did it easily dissolve the rust stains, but it also removed the dark marks/scratches from the edges of my pots and pans.
I should’ve guessed that it would work because I use the gentler liquidy “soft cleanser” bar keeper’s friend on stubborn toilet bowl stains, and that material must be related to what they make white sinks out of.
In fact, if I had been at home, that’s what I would’ve tried first, just to minimize the risk of possibly damaging the sink’s finish.