Update On "Cleaning" Kennedy Halves

A while back I posted about finding some Kennedy half dollars that had a layer of crud on parts of them and asked opinions on removing said crud.

Olive oil was tried and on a couple of the coins worked well.

I then soaked the remaining coins in liquid dish detergent. After about a week in the soap a couple more coins were okay.

I put the three remaining coins back into some liquid soap. I put them up on top of a cabinet. And forgot about them. I found them today. The soap had become an almost solid jelly. When I got the coins out and rinsed them off they had turned black. Where one coin had been laying on another they were still silver, but any surface that was in contact with the soap was black. They've been soaking for about, I believe, six weeks or so.

Gently rubbing with a cotton cloth has turned the black into a uniform charcoal gray, but...

Anyway, the old commercial said soaking your fingers in Palmolive was okay, but they never told you not to soak your silver coins!