Wouldn't a coin need to go through more then being put under a stream of water to be considered a cleaned coin? (I hope) Im not questioning your point, but asking so i know the boundary's
Daggarjon, I was just using a little hyperbole [maybe], although for most serious collectors, any sort of detectable cleaning is the kiss of death for the coin. Looking at the coin is still permitted, as is carefully holding it by the edge while placing it into an approved storage device such as an airtite. Everything else is prohibited. It was easier to be declared holy during the Spanish Inquisition than to correctly handle a coin.
Anybody try putting a coin inside a potatoe and cooked it in the oven (hopefully a coin that is only worth face)??
Nope, never done it myslef. But there are probably ten thousand people who have. There are more ways to artificially tone a coin than there are coin collectors - and most of them have already been thought of and tried.