Has Anyone Found A Valuable Coin That Was Completely Trashed?

Here is a great coin to add to this thread, and make it more interesting. This coin is not mine.
1793 Wreath Cent:

@coinlover, I don't think that cent is *completely* trashed. Encrusted dirt can be removed with a good long soak in distilled water and gently scrubbed away with a toothbrush or toothpick--that is standard procedure when cleaning an ancient bronze coin.

I've found both a 1998 and 2000 WAM in pretty rough shape. The 1998 is AU but has a nasty black carbon spot right on the date that ruins the coin. I have also found a set of blackened 1950 nickels and a 1950-D that looks like it spent at least 15-20 years in circulation.

But when people of the 19th century took rare key dates and counterstamped them into store adverts or scraped off a side for a love token....

Just remembered this one as well--back when I was a cashier, I once found a $50 with a very low serial number... something along the lines of 00000201 low.

Ripped right down the middle and taped back together.

I wonder how many valuable coins have been thrown in wishing wells. The "Its a Small World" ride in Disney World alone must have millions of coins in its waters.

On the 1793, there will be environmental damage, and it will never be a gem. However, it is far from gone, especially considering the rarity level. With careful and experienced conservation it could certainly be improved a ton.