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 Replies: 19 / Views: 5,976 |
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Moderator
 United States
34435 Posts |
It is never good to bet against swamperbob when it comes to the question of a coin's authenticity. With that said, I'm going to go with not plated. I see the scratch and I see the black area. I'm not convinced that this represents an area of flaked off plating though. If it were, I would expect the scratch to be variable in its depth and sharpness as it zigs and zags between the plating and the underlying non-silver substrate.
To answer your questions then:
1. Yes
2. No
I look forward to being proven wrong!
"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
 United States
5362 Posts |
spence You are basically correct. Should NGC have graded the coin? That is a slightly qualified Yes. There is some post strike damage limited to the small Z shaped scratch that was in fact used to peel off a surface lamination in the silver. The fact that the silver lamination is present is visible in the last picture I posted. I chose that picture because it shows rather accurately that a thin sheet of silver (possible debris) was on the surface of the planchet when struck. It extends over the rim onto the edge slightly. If you look at the letter R in the final picture above you can see a line diagonally crossing the R rising from the left to the right. This line is where the scrap meets the planchet. The scratch removed a small detached piece of the lamination above the seam. The black color underneath is silver oxide or silver sulfide. I was wondering if it could be copper fire scale but the planchet would have been annealed and bathed in acid just before striking so it is unlikely to be copper fire scale provided the scrap piece of silver entered the coining chamber with the planchet. I do not believe the scrap was rolled onto the ingot because it crosses over to the edge. I first noticed the mark on the R and followed it both terminations. The seam is actually visible on the very first picture. See below where I highlighted the seam and where it crosses to the edge:  I would have hoped that NGC would have noticed the retained strike through but since they were not asked to slab the coin as an error I can let it slip. The answer to question number 2 is NO - the coin is not counterfeit. It is not a Sheffield plate coin.
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Pillar of the Community
United States
5362 Posts |
I just spoke to the dealer and he is mildly upset. He says that a retained strike through of this nature reduces the value of the coin. I did confirm that an actual Sheffield plate copy of a Morgan dollar would be much more valuable (they are actually unknown right now as a cold fused Sheffield). I know it would be worth more as a counterfeit because NGC is paying a bounty for slabbed counterfeits of $100 so they can remove them from the slab. I was wondering if regular collectors see a retained strike through as so common that it reduces the value of the coin? Edited by swamperbob
03/17/2016 3:12 pm
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Rest in Peace
United States
17900 Posts |
I'm very glad that turned out as it did. Without paying the extra $15 and an additional 5 business days waiting, even a coin with an error won't be listed as such on the holder.
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Pillar of the Community
United States
6370 Posts |
Quote:
To understand the answer to your question you need to understand what Sheffield Plate actually is. It is a sandwich of metal where two thin outer plates of 90% silver (92.5% in the UK) are fused to a central ingot of copper. The composite mass is then rolled as you would a fillet ingot of solid silver. They key to the metals in the sandwich is that they behave as if they were a homogeneous alloy. The metals stretch, bend and perform in all respects as if they were a solid 90% silver copper alloy. I was under the impression that plating would be done after the coin was struck. My thought process was that the plating would be too thin to not crack open when struck and reveal the base metal core underneath. I guess I learned something new. |
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Pillar of the Community
United States
717 Posts |
Retained struck through debris, interesting that it looked similar to Sheffield plate. Thanks for the post!
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Pillar of the Community
United States
5362 Posts |
TypeCoin971793 That happens an awful lot in numismatics. The definitions used in any discussion must be clear to all players or assumptions substitute for facts.
The danger of Sheffield Plate especially the earliest types (because they had very thick plates of silver) was that they were difficult to detect. Electro-plates deposit VERY thin layers measured in microns of pure metal. Sheffield plate is thicker than paper and some reach 1/100th of an inch (10 thousandths). At the time I wrote my book the thickest I had encountered was 7 thousandths. A layer of silver that thick can not be penetrated by XRF. Most Sheffield plate coins are tested with XRF in worn spots or inside of test scratches.
Specific Gravity my old standby test that I use for raw dollar coins is still best for discovering heavy Sheffield plate.
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Pillar of the Community
United States
1962 Posts |
Happen to overhear a dealer and patron next to me at a show over the weekend... Guy showing the dealer some oddities including an XF-AU or so Morgan with a big lamination or strike-through on the cheek (maybe 4 mm? I peeked quickly). Their concurred reaction was more "eh, yuck" than "oh, interesting".
This piece has that very typical early S-mint soft, deep luster... I'm always a big fan of knowing what the surfaces of a given series should particularly present as - it's an easy cheat to help confirm things.
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Rest in Peace
United States
4078 Posts |
Swamperbob, thanks for this very informative post.
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Valued Member
United States
70 Posts |
I was wondering if the ring(sound) of a Sheffield Plate coin would be that of a pure silver coin. I know in this example it is slabbed but if a raw coin were Sheffield Plated would the ring sound different ?
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Pillar of the Community
Canada
4944 Posts |
Very interesting post. I'm not entirely sure how the counterfeiting process works with the Sheffield Plate process, but wouldn't identifying whether the coin is a known VAM be a way to determine whether this coin is a counterfeit or not? Based on the pictures provided, this would be a very highly detailed counterfeit. |
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Moderator
United States
34435 Posts |
Quote:
spence You are basically correct You just made my day! Thanks for posting this topic. "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
United States
5362 Posts |
jamiep You ask a good question: Quote:
I was wondering if the ring(sound) of a Sheffield Plate coin would be that of a pure silver coin. The answer depends on how close to perfect pitch you are blessed with. A hot fused Sheffield plate will ring very well and can easily be confused with the real thing. I suspect the frequency has to be somewhere between silver and copper, but I can not discern a difference. There are Cold fused Sheffield plates which do not ring well at all. These were made by cold rolling the three layers together. They are often encountered partially detached.
Canadian-Banknotes VAM identification would of course work provided the coin is not a forgery made from an original coin. I try never to focus on the details on the die until I rule out all of the transfer methods that can be used to duplicate a genuine coin and I establish how the coin was actually made. If that all checks out then I would go to VAM. In this case (1881-S) that extra effort of determining which VAM number this was did not seem worth it. I determined the coin was a strike through in under 1 minute anyway using a binocular microscope. Sheffield plate is an old technology but if it was used today with an advanced die making technique the results would not be readily detectable unless you used a density check like Specific Gravity to determine the alloy was not solid.
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Pillar of the Community
United States
3184 Posts |
Great post! Do you have any pics of a real Sheffield Plate counterfeit Morgan dollar? |
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Pillar of the Community
United States
5362 Posts |
Tunnioc I wish I could. There are no confirmed examples of a Sheffield Plate Morgan dollar yet discovered. That was one reason I was excited to examine this coin when the dealer called me. He knows that I have been looking for one for years. I have off metal casts and strikes from fantasy to very genuine looking dies. I have electro-plates. I have full weight standard silver counterfeits - but NO Sheffield plate example. The latest dated example of a Sheffield Plate coin in my collection is an 1895 Mo FM example of Charles IIII. That fantasy date is believed (by me) to be an accurate date of issue. My theory is based on the large number of different fantasy dates that were made. In this group are some numeric combinations that could not possibly represent a switched out date. The 1895 is one such date. Those 4 digits can not be rearranged to produce a correct date for any coin from Mexico City that also had the FM assayer initials. Since there was a Sheffield Plate coin (8R) made in 1895, I have always wondered if I could locate a Morgan dollar. I expect that they should exist.
Edited by swamperbob
03/18/2016 10:49 pm
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Posted 03/17/2016 3:04 pm
