i picked this quarter out of circulation last week. it's a 1986 clad proof, with some pretty nasty looking corrosion (?) on both sides. i've been thinking that it would be fun to experiment with different cleaning options on this coin, but first i need to understand what's happened to it. this coin is the perfect specimen for myself (with my novice coin care skills) to experiment on. i'm not really concerned with causing it harm due to its current condition, but it would be neat to restore it (if that's even possible). anyone recognize the damage? the images make the color look light gray/reddish, but it's actually closer to light gray/dark brown. i have already soaked it in acetone to make sure it's not just grime or some other organic deposits. the stuff won't scratch or chip off with light pressure. also, along with my novice skillset comes a lack of proper cleaning materials and chemicals, etc etc. is there anything that can be done?
what kind of results can i expect with an acid dip like that? should i assume that i won't be seeing a mirror finish on the coin after the cleaning process?
That coin is a lost cause no matter what you do to it. The damage is too extensive and has eaten into the metal. If I had to guess I'd say it was prolonged exposure to PVC residue. Even if you dip it, those marks are still going to be there.
Unless you let it soak for an hour or two you should probably still see the mirrors. It isn't that strong an acid. As Doug said though, don't expect the corrosion spots to disappear.
Since the clad layer is 75% copper, 25% nickel like the Jefferson 5 cent CuNi ( except for wartime silver), find a similar crudy jefferson and experiment with e-z-est if you have it, but I have never had any luck with CuNi coins, not even with Nic-a-date. If you don't want to buy E-Z-est then use any decent acid just to experiment ( * DISCLAIMER * I would never use vinegar on any regular coin, but in this case , just to see if E-Z-Est might help, you could use white vinegar on a cruddy current jefferson that you can then spend. Do not use such on any nice coin such as your original post. (* DISCLAIMER*) Jim
probably not a bad idea. but the way i see it, i have an opportunity to toy around with techniques on what amounts to a test coin. even in pr68 condition, it would only be worth a couple bucks, so i'm not out anything. if i fail miserably, i can still spend the quarter, right? i will have to track me down some eZest and give it a shot.
Play around all you want. Make sure you pay attention to before and after, so you can learn WHY certain areas can never come back. Half the battle of more in cleaning coins is recognizing those who cannto be cleaned. Anyone can learn how to use chemicals, the best of them know when and WHEN NOT to use them.
