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 Replies: 26 / Views: 1,147 |
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Bedrock of the Community
United States
15243 Posts |
Quote:
TPGs make no mention, provide no direction, on 'recovered' coins. PCGS categorizes buried coins as ED (environmental damage) code 97. if they can determine, based on the surfaces of the coin, that the coin was buried, they will assign a code 97 to the coin. it will be interesting to see how your coin comes back. this video put out by PCGS discusses code 97. buried coins are covered at about 7 min into it https://www.bing.com/videos/rivervi...9&ajaxhist=0
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Valued Member
Topic StarterUnited States
194 Posts |
They provide multiple reasons for 97-ED with burial being one of them. The examples pictured/provided in their video have serious corrosion/verdigris, etc.
I still stand by the statement that they provided no direct communication on dealing with ground-find coins - like hey, if you dug this from the ground it is automatic ED/Ungradeable. If it has ED/corrosion then absolutely tag it accordingly.
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Pillar of the Community
United States
3388 Posts |
I noted the pebbly texture and before reading responses I wondered if it was counterfeit. Pretty amazing restoration. Isn't gold from the ground more likely to straight grade than copper though?
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Valued Member
Topic StarterUnited States
194 Posts |
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Isn't gold from the ground more likely to straight grade than copper though? Without question. The reference to the KY coins was more of a response to the inference that 'dirt coins' never straight grade. I realize it will be difficult to get any conserved copper dirt coin to straight grade. This one is by far the best candidate I've worked on and that is why I'm sending it in.
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Pillar of the Community
United States
985 Posts |
This is really enlightening -- thanks for posting. Your pic was really striking.
Despite having handled many old copper coins over the years, I'd never seen one with that particular shade of green. That, and the objection to my use of the term "verdigris", prompted me to freshen up on copper coin chemistry.
The revelation that this was a ground coin treated with acetone makes things much clearer. The coin obviously had plenty of verdigris, and what was removed is now being replaced before our eyes. And there had to be at least a little water involved here.
I think the green we see now may be quite temporary -- it will have to darken unless it is kept air-tight away from both oxygen and CO2. The verdicare will slow but not stop the process. The particular resultant shade will depend on the final proportion between copper carbonate and other downstream compounds like copper acetate, copper sulfate and copper chloride (which would require the presence of at least a tiny bit of salt).
I'm really curious to see how PCGS handles it!
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Valued Member
Topic StarterUnited States
194 Posts |
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I think the green we see now may be quite temporary Absolutely, it has been on the window sill in as much direct sunlight as possible since posting. Darkened up a bit already. Coin only saw a brief stint in distilled water to remove any loose debris before Acetone. Although at the dig site - in the ground - it experienced a lot of moisture and freeze/thaw cycles over the past 100 years. FWIW, I've literally seen an LWC change coloration before my eyes in less than 2 hours. Started at the head (closest to direct sunlight) and walked down the bust - it was fascinating to experience. Happy to take another round of comparison pics before sent off if you are interested in seeing.
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Pillar of the Community
 United States
587 Posts |
How long did you do acetone and then how long with Verdicare? I just had some poor results with an 1855 Bradied hair cent and would love to know your secret. Fantastic results!!
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Bedrock of the Community
 United States
81406 Posts |
Perhaps the most impressive "home" restoration I've ever seen.
Edited by Coinfrog
09/17/2023 7:43 pm
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Pillar of the Community
United States
985 Posts |
Acetone made total sense in this case, with decades of solidified ground grunge to deal with. Nothing to lose.
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Valued Member
Topic StarterUnited States
194 Posts |
Quote:
How long did you do acetone and then how long with Verdicare? I do not have a specific formula however the first dunk in Acetone is at least 24 hrs. Then it gets submerged in my 'dirty' tube of VC (don't replace or clean out gunk) for no set time, but never longer than a day. From there it is alternating between Acetone and fresh VC (drops on one side at a time) until I feel the coin shows no progress between rounds. VC may be spot applied only too - precise placement on a target area. Final in VC for protection is typical however in this case, Acetone was final stage to remove any VC chems since I'm sending it in for grading. But each coin is different, especially dirt coppers. I pulled 5 LWCs out of same hole (1917, 3x1919, 1920) and none of them did as well.
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Valued Member
Topic StarterUnited States
194 Posts |
Thanks Coinfrog - means a lot coming from you.
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Replies: 26 / Views: 1,147 |
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Posted 09/15/2023 1:24 pm
