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 Replies: 9 / Views: 1,083 |
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Pillar of the Community
United States
1913 Posts |
Another from the collection with the silver wash worn away from the copper core.  |
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Pillar of the Community
Canada
5239 Posts |
How interesting! How does the weight compare with the original.
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Bedrock of the Community
Australia
21786 Posts |
Picture suggests a high proportion of copper in the core and a thin silver layer over that, which has worn away in the exposed parts of the fields.
It appears to be a die struck fake.
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Pillar of the Community
United Kingdom
2133 Posts |
I remember seeing these in circulation, occasionally.
Nobody suggested they were fake then, just that the metal was badly mixed - they should be 0.625 fine silver and weigh 11.2g.
Can you check your specimen's fineness and weight?
The banks and shops accepted them.
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Pillar of the Community
 United States
1913 Posts |
The measures are very close other than specific gravity, which in turn can be an indicator of fineness. The fake is clearly not a 62% silver alloy, only an alloy of copper and zinc with a silvered wash. Here are some details and catalog data is normally different from real measures. Good coin vs. bad coin: 11.23g weight vs 11.26 2.1mm thk vs. 2.2 28.9mm dia vs. 29 9.85 SG vs. 8.97 Here is an edge picture  Edited by Albert
08/27/2020 7:28 pm
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Pillar of the Community
Australia
1333 Posts |
whoever made these knew what they where doing (very good counterfiet) and the fact that they are extremely close.
Thanku for sharing.
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Pillar of the Community
 United States
7940 Posts |
The numbers don't quite add up (the fake coin would need to be nearly 10% thicker to get that close in mass ... maybe just round-off error in the thickness measure), but indeed, that's a really well done forgery.
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Valued Member
Canada
242 Posts |
Hit that with an XRF and it will likely return .625
Given how clunky home SG tests are, and given how well executed the piece is, I would cast serious doubts on it being fake. I'd rather suggest something like a long-term saltwater dip causing the silver to migrate to the surface, and form said odd toning pattern.
LRC
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Pillar of the Community
United States
1913 Posts |
The thickness measures were rounded, actual values are 2.09 for the good coin and 2.24 for the suspect coin.
I agree about clunky SG calculations because it's not common that many people have the right equipment.
But I do. So I'll do a double check to see if I made any mistakes and be more careful about it.
Here are the new test results:
The good coin SG is 9.914, the coin in question SG is 8.884
So the retest shows even a little more disparity between the two coins. The more accurate test has a stronger value for the genuine coin and a weaker value for the suspect coin.
I like to think of this coin as counterfeit because as follows:
1:It was sold and described by a reliable source as such.
2: I have other unquestionable fakes from the same source.
3: These first appeared in 1966 and as reported in 1968 they were found in Belgium, Netherlands, Switzerland and Austria. Shops and equipment were in Ulm, Germany and Antwerp, Belgium. More than 5022 pieces were made so I regard mine as being one of them instead of a genuine coin being soaked in saltwater.
Edited by Albert
08/27/2020 6:54 pm
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Pillar of the Community
United States
1913 Posts |
I should clarify that I first described this coin in the photo as being copper with a silver wash worn away. But then my measures were questioned, so I went back to do a better job using a more difficult setup. I also did some other math because the coin I have is reported as having been made of an alloy of copper and zinc. So if I'm saying this right, an alloy of 96.5% copper and 3.5% zinc would have a specific gravity of 8.88023. My better and re-tested value is 8.884 so both can be rounded to 8.88. So the SG does match the alloy the counterfeiters used. I don't know sea salvaged coins, so I don't know how long a 1966 coin would have to be soaked in seawater in order for the silver to be raised from the core to the surface. If it was, I'd expect the coin to look corroded instead of what it does look like?
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Replies: 9 / Views: 1,083 |
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Posted 08/26/2020 6:27 pm
