I've been buying a lot of higher grade 'junk' silver Walking Liberty halves over the last year or so. I look through piles of Walking Liberty halves at coin shows and pull out those that would grade at VF or higher. I noticed that a many seem to have dark marks and dark streaks on them. This weekend while I was looking at one I couldn't help but rub my finger across a dark patch, and I noticed that about half of the dark patch disappeared. One or two more light rubs and it was gone. While I come from the never, never, never clean coins. I was wondering about perhaps putting some of these in acetone to see if that would safely remove what appears to be an oily grim on the coins. It all it is is an oil base material, then the acetone should safely remove the grim and not affect the coin surface at all. Right? Any thoughts??
That's what I read in many of the posts. I've also heard that pure grain alcohol (not rubbing or wood alcohol) is safe for coins. I have some Everclear that I could use.
It's my understanding that removal of loose debris does not constitute cleaning. Acetone would probably do the trick, but also possibly a rinse with (distilled) water.
@BadThad Organic solvents are good for removing organic contamination and water is good for removing inorganic contamination. With that being said, any pure organic solvent is suitable for cleaning coins. If you are concerned about schmutzy stuff on the coins, rubbing alcohol will do a good job and shouldn't leave any residue FROM THE SOLVENT however anything taken off the coin can redeposit if the solvent is dirty. Acetone does a better job at removing organic stuff than alcohols do, but methanol (wood alcohol), ethanol (everclear) or isopropanol (rubbing alcohol) will remove more organic material than water. Just make sure your final rinse is CLEAN.
I've got one coin sitting in a glass dish of acetone right now. After about 45 minutes I couldn't see that is done much of anything. I'll let it sit some more and see what happens. Thanks for all your comments.
Ya might want to cover that dish with something, so that the acetone doesn't all evaporate away, and re-deposit any gunk that it might have taken off. I keep an old 'relish' jar and cap handy.
Good Gosh. Walkers are at least 70 years old. During that time they've been handled many thousands of times and have wound up in some dealer's pile of halves and sifted through who knows how many times. The dealer put them where they are because there's nothing special about them. Do you really think that taking them to your sink and washing them off by hand with soap and water is going to damage them? Save your extra efforts for something worthy of special handling.
If you don't damage the surface, it's not cleaning, it's conservation. This is completely proper and acceptable by everyone if done properly. You could either do as you did before and simply rub it off, or use a q-tip dipped in acetone. DO NOT use this method on MS or proof coins, it will damage them. But well circulated coins are fine.
David - you'd be surprised at what I've found going through these piles of halves. I've almost completed a complete set just by going through junk silver and that includes three 1946 double dies. I attached a photo of one I got this weekend going through a bag of junk silver and paid $7.50 for it. And I'm working on my second Mercury dime book. In the first book I got every dime but the 1916-D and the 1921-D. I'm 7 dimes away from completing my second Mercury dime book, all collected from 'searched' piles of junk silver.
What happens when you've removed the dark patch? Answer: a light patch because the underlying surface hasn't patina'ed at the same rate as the rest of the coin. And a more-obviously unoriginal (and obviously cleaned) coin than it was before. Success isn't always desirable.
So here is what happened with the acetone soak. Not all the dark sports were removed, but some oily smudges were removed, especially across the breasts, as well as some yellowing in the lower region of the front. I didn't do any rubbing. It was just the soak and rinse. If you look closely a couple of spots disappeared, but many were untouched.
My comment wasn't about rarity or otherwise hard to find coins, it was about the condition and how you aren't going to damage an already impared coin by washing it by hand.
David - While I agreed to a point, I wouldn't want to turn any coin from a FINE to a FINE that was cleaned. Harsh washing could give a coin a cleaned surface with a lot of micro scratches. Even rubbing hard with a finger can add streaks of micro scratches. Again, probably not that big of a deal with middle to lower grade coins. It's not something I'd want to ever get into the habit of doing.
Gentlemen/Ladies: I have a lot of cheap foreign coins (the type you buy on eBay by the pound) which I am going to use for craft projects for my grand children. They have no numismatic value (and my grand kids won't care) so I want to clean them as cheaply and easily as possible. The copper coins are no problem, nor are the shiny silver looking coins. My concern is the coins which appear to be brass (probably some alloy). I can clean them (make them shiny) with Brasso or a Dreml, but I am seeking some less time consuming way to brighten them. Any suggestions would be appreciated. Again, there is no numismatic value to these coins, they are common, current date, coins, mostly from Europe and the Middle East, I just want to make them shiny for projects for the kids. Thanks in advance for any suggestions.
You have a mix of metals. Some chemicals - like acetone are gentle on silver while it is very harsh on copper. Zinc is another metal that is very reactive to chemicals. If I was in your place I'd use a polishing system (vibrator polisher) that is used to polish ammo brass. Use corn cob as a medium. You show get a nice polish across all the coins without the risk of a chemical distroying any if them.
