De-chroming ?

[Mark]

The other thing to avoid is not to tell significant others what is in the dish by the back door or you will find it clean and you will be scrabbling for the work in the grass

That sounds like the voice of experience

Your mention of copper makes me wonder if Ferric Chloride would would ? That's used to etch printed circuit boards and I believe is the etchant for brass photo-etched parts.