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 Replies: 19 / Views: 37,992 |
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Pillar of the Community
United States
5362 Posts |
Since I originally commented on the diagonal grip marks - I can say with 100% certainty - what you have here is NOT the grip marking that I was referring to. The grip marks are usually cross the entire edge side to side. They are also usually single lines with a physical separation that is approximately the same length. To me that looks like post strike damage of some sort. It would not be classical "adjustment" because the filing would have most likely have been on the face of the blank. As far as I have been able to determine the weighing and adjustment step happened BEFORE the strike. I have created a quick sketch to show what I mean. I have none of the "late" forgeries with the diagonals at home so I have no pictures.  The diagonals are shown on top. They occur on top of the edge on half the edge. The other half typically has no trace of the diagonals. I also included a possible reason why at times some people miss the overlap. The easiest overlap to spot is the type that is NOT aligned. But there are aligned laps as well which are harder to spot. There is usually some trace but they can be overlooked or easily eliminated by edge damage. They are virtually impossible to spot on a worn edge. However if one side is aligned so is the other. The only exceptions to this rule are some of the Revolutionalr issues that were made with slightly IRREGULAR segments. What this all points to is the necessity of being very familiar with the edges of MANY different coins. I have look at literally 100's of thousands of these coins over the 50 years I have been collecting. |
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Pillar of the Community
 United States
1156 Posts |
Thanks all, for the responses on the first edge picture. I clearly misinterpreted swamperbob's description of the grip markings. The overlap on this coin is clearly visible on the opposite side and about the same length as the damaged section. (Sorry I didn't take a picture) At the peak of its wobble, the overlap was fully offset instead of superimposed. Here's the obverse, the bad section starts at 10 O'clock and runs to 1 O'clock.  |
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New Member
United Kingdom
8 Posts |
I have the attached edge pictures of what is alleged to be an 8 Reales Charles III Madrid bust type. My concerns about the coin are its weight 24.4gms diameter 38mm. I would normally expect a weight of 27+/-0.2gms and a diameter of 40mm. I have others mostly Spanish Colonial that all have the correct weight As you can see the beading at the edge of the coin is absent it would appear 1mm around the edge has been removed, but the edge markings have remained? Any views would be useful     |
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Pillar of the Community
United States
1523 Posts |
That really is one homely lookin dude.
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Pillar of the Community
United States
3499 Posts |
Roncoin- Is that the edge pic of the 1782 Madrid 8?!?! If I am not mistaken, the 8's struck in Spain had a totally different edge type from their colonial counterparts. I have a feeling that that 8 is quite fake.
Halfwitty- Yup, the royals were not that good looking. That is what generations of inbreeding will do to a bloodline.
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Pillar of the Community
United States
5362 Posts |
Given the reduced diameter and weight loss. I would postulate that the coin was an original which was filed around the full perimeter to steal silver. I also wonder if it was subsequently re-edged with approxomately the RIGHT design. I have seen a re-edged orignal before but the edge is not as good looking as this one. Does the entire perimeter look this good? Are there 2 overlaps? Are there any irregularities?
If the edge type is incorrect (I simply don't know enough about how continental mints edged their 8R) it would tend to support a re-edging by someone who was fimiliar with colonial edges.
Edited by swamperbob
03/27/2010 11:15 pm
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New Member
United Kingdom
8 Posts |
Thank you all for your comments. The edge is of the same coin as the pictures (1782). Here some additional pictures of the date region and especially of the number 8 in the date. As you can see the date appears to be a double strike. The 8 has been very much flattened and worn, but it does have the "curly" serif at the top that is common to colonial 8s. My density calculation based on measurements indicates 9.60gms/cm^2, I will try to do a more accurate density measurement later today. I will also try and post more edge pics later today. At the moment I cannot see an overlap. I agree that this may be an example of clipping.   |
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New Member
United Kingdom
8 Posts |
As a followup to previous posts. I have now done careful water displacement density measurement. The density of the coin is 9.38gms/cc. If this coin were of an alloy 0.900 silver with say copper I would expect a higher density. Swamperbob here are some more pictures of the edge. I have taken these scans around the edge at four positions orthogonal to each other. I still cannot find an overlap point.Any further comments on the authenticity of the coin would be useful.     |
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New Member
United Kingdom
8 Posts |
A little additional update on my coin,see my posts above. While earlier I agreed with Swamperbob that this might be an example of edge clipping (silver stealing), with a new edge pattern added after, in the light of new evidence there is now a problem with that conclusion.
While the weight difference from 27grms to 24.4grms and the reduced diameter could be accounted for by the removal of 1mm from the radius all around the periphery, this does not account for the measured density of 9.38grms/cc^3. If the coin was of the correct alloy (silver-copper) with a weight fraction of 0.9, then the density would be 10.3grms/cc^3 (cf silver 10.5grms/cc^3).
The precision density measurement of the coin would suggest the coin is made from an alloy with a weight fraction of 0.300silver-0.700copper. That alloy has a density of 9.32grms/cc^3
The main question-Is the coin a fake? Or how can the radial clipping explanation be reconciled with the density measurement?
Interested in any comments or a check on my calculations.
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Pillar of the Community
United States
5362 Posts |
There are a couple possibilities of course. There were Debased copies made at branch mints which usually resulted in someone getting fired or hung. In that case the dies would be real, it would be mint made and issued so the coin would be considered REAL but debased. In that case, a second forger would have had to steal silver from the rim. That scenario is simply less likely than a simple start to finish forgery.
The new data you provided helps me to focus on the forgery alternative for a few reasons. First, the low specific gravity. This is a fairly common SG for an early forgery before the advent of German Silver. Second, the doubling I see on the detail of the date looks like what you often see on low pressure strikes like those made in rocker presses. The rocker press was small and compact but a forgery often required repeated strikes and as the coin enlarged because of the pressure the details started to go out of line. Third, now that I see more of the edge it is obvious that the edge of the coin was peaked. The blank was larger in diameter at the center than either edge - that points to a blank that was not made using a standard punch. The mints did not file the edges because they made the edge design difficult to transfer.
So, at this point I am leaning toward a well made early contemporary counterfeit. Coronado does not list a contemporary copy of the 1782 Madrid 8R so you could have a brand new type there. It might take an XRF to tell for sure.
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Pillar of the Community
United States
3499 Posts |
If the coin was real and re-edged or if it is just an unknown type of counterfeit made in Spain then this does point to the fact that Colonial 8's were well known on the continent. Very interesting!
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New Member
United Kingdom
8 Posts |
Swampbob and Archraz, thanks for both replies.
I collect Bank of England $/5s. A subset of my collection is copies with clear date show-through from the original 8 Reales. I then match these as pairs with Spanish or Spanish Colonial 8 Reales of the same date. I have BoE$/5s with clear show through from 1772 to 1810.(Charles III, Charles IV and Ferdinand VII. From Seville, Madrid, Mexico and Potosi.
That preamble is to help explain my next step. We have today made precision density measurements on two BoE$/5s. One with Seville 1779 show through and the other Madrid or Seville (1779 or 1772).
The densities are 10.26grms/cc^3 and 10.34grms/cc^3.
An Ag/Cu alloy would be 10.32.
I now await the "authentic" coin money back decision of the reputable house that this was purchased from!!
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Pillar of the Community
United States
5362 Posts |
The SG's look good to me (within normal tolerance) - was that last comment a joke?  |
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New Member
United Kingdom
8 Posts |
Swamperbob. At the time of writing the last sentence of my last post was a sort of cynical joke. But I can now say the reputable house has agreed on the evidence presented that they have made a mistake and have agreed to return my money.
Yes I agree, the densities of the two genuine 8 Reales (10.26 grms/cc and 10.34grms/cc) are within tolerance. They provide the overwhelming evidence that the coin in question at 9.38grms/cc is fake.
It is a strong indicator that the "fake" coin is made from a an alloy with a weight fraction of 70 copper 30 silver. (Density of that alloy is 9.32grms/cc)
From contact with other collectors I am told that relatively recently a newspaper in Madrid produced a medallion copy of an 8 Reales as a give away. Maybe it is a modified version (edge added) of one of those. Anybody know anything about that?
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Pillar of the Community
United States
5362 Posts |
OK I guess I am a bit slow here. The coin you are referring to was the original subject with the bad edge. I am glad you are getting your money back. Check with the owner and see if they have any interest in selling the coin as a fake. It would be interesting to see if the forgery is contemporary or modern.
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Replies: 19 / Views: 37,992 |
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Posted 03/17/2010 8:30 pm
