66-67 b-body bucket seat trim question?

Hello I have a 66 coronet with factory bucket seats, was wondering if the trim on the back panel of the seat is stainless? My trim appears to have oxidation on them almost looks like they were crome plated from factory, I haven't tried to polish the seat trim yet, my door panel trim looked the same but polished out like a mirror finish however a magnet still stuck to it (I think a magnet stuck to my windshield trim also). A friend of mine said it is probably a low grade stainless, anyone have any thoughts on this.

anyone?

I looked at the bucket seat trim on my 67 Satellite (16k mile unrestored survivor) and it's chromed plated steel, not stainless.

FYI, They didn't chrome plate stainless steel from the factory (it's just polished).