Posted 06/07/2010 9:45 pm
Sorry, but the damage has been done. Toning is toning, and silver sulfide is silver sulfide; garlic is loaded with sulfur-containing compounds, and it's those compounds that have reacted with the surface of the coin, producing an effect that is chemically identical to "natural" toning. Anything that removes the "garlic-induced" toning will remove the natural toning as well.
I'm not sure the AT crowd have tried deliberately using garlic to tone a coin, but it's not something I'd recommend, since it would leave the distinctive garlic smell behind.
Acetone won't remove toning/tarnish, either natural or garlic-induced. It will, however, remove the organic sulfur-containing compounds from the coin's surface. If your friend had washed the garlic juice off with acetone instead of "He just wiped it off and placed it again in pocket", the coin would not have changed appearance at all.
As it stands, you've really only got three choices:
1. Dip it in tarnish remover. That'll give it the blast-white appearance of a cleaned coin, and is probably the least appealing of these options. You could try selectively cleaning the garlic patches with a cotton swab or fine paintbrush soaked in dip, but you'd need a steady hand. A "partially cleaned" coin often looks even worse than a blast-white one.
2. Leave it alone and see what colour it eventually turns. If you do this, you might want to swish it in acetone so at least all the garlic juice has been removed. This would be my choice.
3. Artificially tone it, either by dipping and retoning or retoning it as-is. I really wouldn't recommend doing this, either, since it has the potential to be both deceptive to the coin's future owners and to be destructive to the coin itself.
I'm not sure the AT crowd have tried deliberately using garlic to tone a coin, but it's not something I'd recommend, since it would leave the distinctive garlic smell behind.
Quote:
(please NOT blast white, so acetone is really out)
(please NOT blast white, so acetone is really out)
Acetone won't remove toning/tarnish, either natural or garlic-induced. It will, however, remove the organic sulfur-containing compounds from the coin's surface. If your friend had washed the garlic juice off with acetone instead of "He just wiped it off and placed it again in pocket", the coin would not have changed appearance at all.
As it stands, you've really only got three choices:
1. Dip it in tarnish remover. That'll give it the blast-white appearance of a cleaned coin, and is probably the least appealing of these options. You could try selectively cleaning the garlic patches with a cotton swab or fine paintbrush soaked in dip, but you'd need a steady hand. A "partially cleaned" coin often looks even worse than a blast-white one.
2. Leave it alone and see what colour it eventually turns. If you do this, you might want to swish it in acetone so at least all the garlic juice has been removed. This would be my choice.
3. Artificially tone it, either by dipping and retoning or retoning it as-is. I really wouldn't recommend doing this, either, since it has the potential to be both deceptive to the coin's future owners and to be destructive to the coin itself.
Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis
Sap covered it pretty well. One more option if the crown is circulated and not of very high value. Your friend can carry the coin as a pocket piece for a couple weeks, mingling it with other change. A circulated coin should not have noticeable wear after a couple weeks but the toning should be lightened.
