Cleaning and Stain Removal - Stainless Steel Tranished?

Used a friend of a friend contractor while we were on vacation to retile our bathroom. Contractor did something to the kitchen sink. Looks tarnshed. He says he wasnt mixing grout in the sink but he was cleaning a rag.

What might have been on the rag that would tarnish a stainless steel sink? He claims nothing can tarnish stainless steel in that fashion.

Stainless steel is made in a variety of alloys and some of those are not completely rust proof or they can "gray".

I've seen SS bolts rust on the shelf and had SS sinks rust or oxidize.

I'm sure there are solvents and so forth that might accelerate the process.

I'd try some of the various stainless steel cleaners or polishes and see how it goes.I doubt it is a permanent situation.Sorry but I can't really recommend a particular product.

strong acidic cleaners can damage stainless....if he was mixing grout or dumping it out in the sink there would be more issues than just appearance...may of been a cleaner to remove grout haze

Try using Comet on it. You can buy it at any store that sells cleaning products. If that doesn't work try a Brillo pad or steelwool as a last resort. Not to many people use Comet but it's been around for more that 50 yrs.

be careful using strong abrasives or pads on stainless...only as a last resort