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 Replies: 14 / Views: 652 |
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Pillar of the Community
Sweden
1280 Posts |
So I kind of like this coin. Wondering if I will try to buy it. The toning looks colourless. The details look very good on this coin, no mark or big scratches, but it looks weak. Is it a thick layer of patina over? Is the surface destroyed under? Dont know where to post this. What got me hooked is that the coin shows little wear.   Edited by Moniker
11/11/2024 4:55 pm
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Moderator
 United States
157664 Posts |
Very interesting.  |
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Bedrock of the Community
United States
94367 Posts |
Difficult to evaluate from these pics.
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Bedrock of the Community
United States
15745 Posts |
Moniker, I've encountered many silver coins with a similar appearance. I believe that they have been exposed to some chemical which has created a heavy patina on them. The green tinges are especially worrisome. Since there has been a chemical reaction with the coin's surfaces, I don't think it can be removed without removing the superficial layers of the coin. It would probably be ugly afterwards. However, this is just conjecture on my part - I've never tried "dipping" such a coin. It may be beautiful afterwards. I would look for a different coin.
Inordinately fascinated by bits of metal with strange markings and figures
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Pillar of the Community
 Sweden
1280 Posts |
Thank you Hondu, I guess u are right. The layer looks thick like it has been under ground. looks unc but enviromental damage
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Moderator
United States
32709 Posts |
This subforum is a perfect spot for this @mon.
I've seen the same thing with silver coins rescued from old leather wallets and coin purses. Much like @hon, I haven't cleaned them though so not sure if this is just on the surface or not. A long soak in acetone would be a good first step if you want.
"If you climb a good tree, you get a push."
-----Ghanaian proverb
"The danger we all now face is distinguishing between what is authentic and what is performed."
-----King Adz
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Bedrock of the Community
United States
94367 Posts |
Agree, these surfaces are often seen on uncirculated examples.
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Pillar of the Community
United States
1150 Posts |
Looks like a dirt coin, I've pulled many silvers with a similar appearance. As stated, specific chem in the ground leached on the coin. Possibly exposed to a fire (high heat). If there is any copper in your example I'd say the blackening on the face is likely there to stay if fire scale.
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Pillar of the Community
Canada
5124 Posts |
Good old silver cancer .. Terminal diagnosis.the coin best get Its affairs in order .  |
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Bedrock of the Community
United States
54905 Posts |
It looks like environmental damage. Maybe it's been buried at one time?
Errers and Varietys.
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Pillar of the Community
Sweden
1280 Posts |
To bad I kind of like its appearance  but I don't like it 60 dollars much  might be colours on it, this pawnshop take the most uninspiring photos Thank you all for the info interesting, I don't know if it contains copper but its .800 silver |
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Moderator
United States
157664 Posts |
Quote:
but I don't like it 60 dollars much That money is probably better spent elsewhere.  Quote:
I don't know if it contains copper but its .800 silver I cannot imagine it being alloyed with anything else but copper. 
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Pillar of the Community
United States
1702 Posts |
IMO severe environmental exposure. We see the Ag/Cu alloyed piece with the copper counterpart being FORCED to the surface as the more oxidative metal copper will try to leach out of the coin in certain extreme exposure conditions which is the main principal on why we see silver surface enrichment effects on older ~90%Ag/~10% Cu alloy coins. The black areas are AgS & AgCl with sulfur and chlorine being the two most omnipresent environmental contaminants on any coin's surface. AgS & AgCL are inert and difficult to remove even with ultrasonic treatment. Any solvent treatment would be worthless other than removing the copper oxide (i.e., green) coloration. Unfortunately today coins of this nature receive the NGC/PCGS "environmental damage" tag and hence this coin is unwanted by many.
I have a new paper coming out shortly with many SEM/EDS analyses explaining all this and once published will notify CCF administrators.
John Lorenzo
Numismatist
Edited by colonialjohn
11/14/2024 11:17 am
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Moderator
United States
32709 Posts |
Quote:
I have a new paper coming out shortly with many SEM/EDS analyses explaining all this and once published will notify CCF administrators. Looking forward to reading this!
"If you climb a good tree, you get a push."
-----Ghanaian proverb
"The danger we all now face is distinguishing between what is authentic and what is performed."
-----King Adz
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Pillar of the Community
Sweden
1280 Posts |
Me to thanks for the edjucation  |
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Replies: 14 / Views: 652 |
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Posted 11/11/2024 5:01 pm
