I had a slightly backed up sink. So I put a glug of bleach in the
drain and water, and let it sit. Usually works, then plunge later.

But oops. There was a silverplate teaspoon sitting in the murky water.
It came out with the bowl of the spoon looking like it has a whitish
coating, and back greenish. Now, this is one of an odd-lot of flea
market silver, so no big loss. Just wondering if there is any hope of
rescuing it. No, replating is not an option for maybe a two -dollar
spoon But is is, or was, silver.