I don't think it will be that drastic. A "ding" will only register as a 'change in the characteristics, but NOT to the identity, IMHO.
the 'ding" would be annoted as a change in info, but niot in identity It is liken to the fingerprinting to identify the human. Cut off the fingers, you still have other means. In this case, I imagine "machine" would take note of the "ding,", and add the info to the data, at the same time identifying the coin as the original.
As far as the price, yes, it is rough, but consider this: You have a sizable collection of gold, silver, and very rare and expensive coins. Then the price becomes another item in the insurance protection of said collection. It could always be identified as being one of yours that was stolen, some time in the past. Can you do that with any of your present collectibles? Anyone?
Dick