02-12-2023, 06:47 AM
That is an interesting question you pose there Martin. My answer is that in most cases you shouldn't use it. However I don't believe it does any actual damage to a coin so if a coin has a blemish or is marked possibly by previous bad handling or cleaning then its appearance can be improved. I believe similar products are probably used for conservation purposes by NGC and PCGS. Also when you purchase a coin you have no idea what it might have been subjected to by previous owners. I once bought a 1953 NZ proof set off ebay, contained in one of those special capital plastic type holders. They were really nice and I broke them out and put them in Saflip coin holders. I left them for a while and next time I checked on them the coppers had developed carbon spots as well as the threepence. I suspect the person who put them in the holder originally might have blown/spat on them or something to remove any bits of fluff or debris. I was able to remove the carbon spot from the threepence but no such luck with the coppers (probably should have used acetone on them after breaking them out.)