Either way its one heck of a grab. I recommend a product called MS-70. I just tried it on a Proof SAE that had hazing and blotches of something on it. The results were amazing!! Good Luck hope it comes back PF or even PL.
I'd have to say not a Proof. IMO the strike isn't good enough and the corners of the rims do not appear to be squared off. I'd have to go with PL. I think I would send that one in to NCS though.
Bad idea, ammonia turns silver black. I could see using acetone, maybe. But I doubt it will be much help in this case.
I currently have a coin at NCS, when it comes back I will update my thread. I am anxious to see what they can do!
NCS did an amazing job on an early Mercury dime of mine, so I'd be happy to use them again.. even for just a consult. I'll pull the half dollar out of the acetone in a few hours.
Proof is what I would grade it??? I seen grades in PR-55 to PR-67DC in seated half's.but this one should be PR-60 Cameo??? at the least.
At first I thought this was not a proof (rims don't look square enough). The more I look at it the more I think it might be (particularly the strike characteristics, as well as the mirroring inside the shield). I'd check two sources to try and tell. First, Heritage Archives. Second, Breen's Proof Encyclopedia.
Here's a link to the Heritage archives for proofs from this year: http://coins.ha.com/common/search_r...SI_Titles&Ne=304&N=51+790+231+373&Ntt=1871+pr I would look for die markers in these coins (Breen probably mentions them), and try to match to your coin. Of course, we need to find out if proof dies were reused to make business struck coins to eliminate that possiblitiy.....
I'll post an example later this evening of "before and after" using the Windex method. Agree, ammonia isn't something you would want the coin to sit and soak in. However, a quick dip followed by extensive flush with clean water provides some remarkable results, especially on proofs. Doesn't seem to do much on uncirculated coins, especially copper. Acetone being a solvent, it will disolve all sorts of contamination from the surface of a coin, but if that contamination has already reacted with the metal (PVC damage for instance) part of the coin is going to be removed along with it. I supose for some applications it would be great, in particular, tar or other oil based adhesions on the surface of a coin. Much like you observed, I don't think it will do much for the coin in this thread.
Here's the soaked/rinsed photos. Noticeable improvement. May do another round tonight. Here's the original one again. Note how the LIBERTY is so grungy and all. Appreciate all the tips/thoughts!
If you send a dirty but otherwise un damaged coin to ncs, can they conserve it in such a way that it can still go on to get a complete grade, not just a detailed/cleaned grade?
They don't guarantee that, but they are professional conservators that really do good work on coins. So more often than not, it comes back without a details or genuine slab.
Just picked up the Breen Proof Encyclopedia from a local used bookstore for cheap. Unfortunately, the text is rather limited and no pictures for this year. Think the auction archives is the way to go here.
Lucky. There isn't a single book store around me that sells coin books and the coin stores here don't either.