Another NEWP, and medal/exonumia guru advice (conservation question)

Which is exactly what you'll get with xylene. And understand, I'm not trying to discourage you from doing your own testing first - full speed ahead with that ! All I'm trying to do is offer assurance that xylene is perfectly safe and will not harm the medal in any way

 

Thanks for the confirmation

Yeah I know Mike, you don't agree on that point. We are just gonna have to agree disagree on that one.

I'm surprised you'd say this. Yeah, MS70 will remove gunk and oil. But, MS70 is also infamous for turning copper blue ! MS70 works great on silver and or nickel, or CU coins. But MS70 on copper is a big no-no !

 

Easiest place to find it is in a paint store, as that's it's primary use. Simply go in and ask for a small can of xylene. They usually sell it in quarts and gallons but some might have pints.

 

Verdi-Care was specifically designed to remove verdigris, not for general cleaning.

 

All I can say is this - every one I ever used it on turned blue - every one. I've seen turn cents blue straight out of mint packaging, both Mint Sets and Proof Sets. And read countless reports from other collectors over many years of it turning their copper coins blue. And while I've never submitted any myself, many others have had copper coins body bagged or detail graded by NGC and PCGS because MS70 turned them blue.

Could all those coins have had something on them ? Yeah, I suppose so, but danged if I know what it could be that it would be on all of them. But in the end, would it matter if that's what the reason was or not ? To me, the only thing that matters is that it happened at all - not why it happened.

 

Any and all toning can be removed in seconds with a coin dip. And yeah I know, people say you can't dip copper. Well horse puckey - you can ! IF you know how.

That said, I have no idea if that is what Mike does or is even suggesting. He is probably one of the most knowledgeable people there is or ever has been in numismatics when it comes to cleaning coins. Even so, there's a thing or two that he and I disagree on - but not much.

The procedure for acetone, xylene, alcohol, even distilled water, is basically the same. I have provided it here in this thread -
https://www.cointalk.com/threads/proper-acetone-procedure.193708/

 

I'm not disputing that Mike, I agree 100% on that count. There's lots and lots of copper coins with natural blue or a shade of blue toning.

The only thing I'm saying is that I've personally never seen a copper coin that if MS70 was used on it - did not turn one shade of blue or another. Some have a purplish cast to them, but that's still a shade of blue.

Could your experience, or anybody else's be different than mine - sure it could. All I can do is relate mine.

And by the way, you can go back over a period of 20 years on both the NGC and PCGS forums and find the very same thing I'm reporting here. That MS70 turns copper blue.

 

Mike I wanna add something else here. You said -

So what you're saying is that some copper coins have something on them, and whatever that something is, that's what is reacting with the MS70 and causing the coins to turn blue. And at the same time, you're saying, or at the least implying, that not all copper coins turn blue if MS70 is used on them - because they don't have that "something" on them.

Well Mike, when you say that you've treated some copper coins with MS70 and they did not turn blue - I believe ya. I don't doubt your word a bit, I trust ya too much to do that.

But, think about this. Perhaps, just perhaps, the reason that some of the copper coins you have treated with MS70 did not turn blue, is specifically because they had "something" on them that prevented them from turning blue. I mean both scenarios are equally likely. If there's something that can cause the blue, it's just as likely that something can be preventing it.

Also think about the fact that the reason you are using MS70 on the copper coins - IS because there is something on them that you are trying to remove. I mean, the reason you're using the MS70 to begin with is because there is something there. If there wasn't anything there you wouldn't be using it at all.

So which scenario seems more likely ?

Now consider this. As I said above, I've used MS70 on copper coins I took straight out of mint packaging. There was nothing, absolutely nothing that could be seen on the coins, and yet they turned blue - every single one.

Now could it be that there was a residue on the coins from when the planchets were washed that was not rinsed off completely - and that residue is what caused the coins to turn blue because it reacted with the MS70 ? Yeah, it could be. I readily admit that. But I will ask again - does that matter ?

The whole point is that no matter what, there is a risk, a risk that if MS70 is used on copper coins that those coins will turn blue.

However, if you use xylene on the copper coins, it will do every bit as good a job as the MS70 will, if not a better job of it - and there is no risk at all ! None, zero !

So which would be the better option ?