@CaptHenway said:
Let me begin by saying that I absolutely love this pair! No question a legitimate major Mint error. I would be pleased and proud to own it.
And now, a major mystery. Look at the struck side of the Half Dime. Note the ring of peripheral toning near its circumference, typical of many a silver coin of the 19th Century.
On this Half Dime, much of the periphery is no where near the periphery of the half dollar. So how did those areas acquire peripheral toning?
TD
Slight difference in the alloy mix? Maybe the two pieces were stored separately? I think you would need to know something about how/where it has been for the previous 160 years to be able to give a comprehensive answer to that one.
Sean Reynolds
I wonder if the crushing effect of the upsetting process changes the molecular structure of the metal near the rim in some way that affects its toning? Think about those Morgan dollar that have the shiny "doubling" outside the stars, the date digits and the lettering. In those cases metal was partially struck up into the stars, digits and letters and then dragged, kicking and screaming, out past the corners of those design elements where the outlines did NOT tone because their molecular structure had been changed.
TD
My best guess is very similar, but I suspect that the lighter crescent at the top of the half dime planchet is where it expanded beyond its original size and shape. And that the same effect is less pronounced closer to the rim because the collar constrained the expansion of the planchet to a greater extent near the rim than at the center of the dies.
Obviously the Half Dime planchet spread some as it tried to fit into the Half Dollar planchet during this abnormal strike. However, IMHO there is little or no normal outwards expansion in the center of a coin during a normal strike of a coin with raised central devices on one or both sides.
This is based upon my study of the 1922-D cent dies, many of which were severely overused. There are many reverse dies in very late die states where the wheat ears and the legend E PLURIBUS UNUM are greatly degraded via outward expansion die flow, as well as the letters of UNITED STATES OF AMERICA closest to the wheat ears. However,these dies are often still near normal in their centers. I believe that this is caused by the metal in the center of the planchet moving up into the central device of the hammer die and down into the central device or lettering of the anvil die, rather than outwards into the rim.
Numismatist. 50 year member ANA. Winner of four ANA Heath Literary Awards; three Wayte and Olga Raymond Literary Awards; Numismatist of the Year Award 2009, and Lifetime Achievement Award 2020. Winner numerous NLG Literary Awards.
It was in the Heritage Auctions 2024 Platinum FUN ‘Auction Previews’ but was removed…
mikebyers.com Dealer in Major Mint Errors, Die Trials & Patterns - Author of NLG Best World Coin Book World's Greatest Mint Errors - Publisher & Editor of minterrornews.com.
@CaptHenway said:
Let me begin by saying that I absolutely love this pair! No question a legitimate major Mint error. I would be pleased and proud to own it.
And now, a major mystery. Look at the struck side of the Half Dime. Note the ring of peripheral toning near its circumference, typical of many a silver coin of the 19th Century.
On this Half Dime, much of the periphery is no where near the periphery of the half dollar. So how did those areas acquire peripheral toning?
TD
Slight difference in the alloy mix? Maybe the two pieces were stored separately? I think you would need to know something about how/where it has been for the previous 160 years to be able to give a comprehensive answer to that one.
Sean Reynolds
I wonder if the crushing effect of the upsetting process changes the molecular structure of the metal near the rim in some way that affects its toning? Think about those Morgan dollar that have the shiny "doubling" outside the stars, the date digits and the lettering. In those cases metal was partially struck up into the stars, digits and letters and then dragged, kicking and screaming, out past the corners of those design elements where the outlines did NOT tone because their molecular structure had been changed.
TD
My best guess is very similar, but I suspect that the lighter crescent at the top of the half dime planchet is where it expanded beyond its original size and shape. And that the same effect is less pronounced closer to the rim because the collar constrained the expansion of the planchet to a greater extent near the rim than at the center of the dies.
Obviously the Half Dime planchet spread some as it tried to fit into the Half Dollar planchet during this abnormal strike. However, IMHO there is little or no normal outwards expansion in the center of a coin during a normal strike of a coin with raised central devices on one or both sides.
This is based upon my study of the 1922-D cent dies, many of which were severely overused. There are many reverse dies in very late die states where the wheat ears and the legend E PLURIBUS UNUM are greatly degraded via outward expansion die flow, as well as the letters of UNITED STATES OF AMERICA closest to the wheat ears. However,these dies are often still near normal in their centers. I believe that this is caused by the metal in the center of the planchet moving up into the central device of the hammer die and down into the central device or lettering of the anvil die, rather than outwards into the rim.
That makes sense. And the fact that the half dime planchet was not elongated in striking tends to back you up.
BTW, have you noticed the darkish patch on the center of the obverse? It pretty much matches up to the darker areas on the reverse. Now I'm really confused...
Andy Lustig
Doggedly collecting coins of the Central American Republic.
Visit the Society of US Pattern Collectors at USPatterns.com.
@oih82w8 said:
I am pretty sure that the REV Die is the anvil position and the OBV is the hammer. I have been wrong before. Perhaps @dcarr could enlighten us?
Traditionally, the reverse die is the anvil die. However, there are exceptions. The question is whether this is one of the exceptions.
Trivia question: How can you tell after the fact which die was the anvil die?
That's a great question @jonathanb! How can you tell which die was the anvil die after the fact?
A coin press could operate with the dies either way.
Typically, as the last step in the stamping cycle, the lower (anvil) die pushes the struck coin out of the collar.
A careful examination of a coin's edge can reveal which direction the ejection "slide marks" go, and that can infer the orientation of the dies.
@oih82w8 said:
I am pretty sure that the REV Die is the anvil position and the OBV is the hammer. I have been wrong before. Perhaps @dcarr could enlighten us?
Traditionally, the reverse die is the anvil die. However, there are exceptions. The question is whether this is one of the exceptions.
Trivia question: How can you tell after the fact which die was the anvil die?
I've recently noticed SLH have better rims on the reverse than the obverse. Perhaps by wear patterns At least that appears to be the case with 1855/54 SLH. However, Barber halves usually wear into the reverse lettering and design before the obverse, so I'm not sure if this is related to being struck with the anvil die, or differences in die design and metal flow.
My other guess would be checking the rims or checking flow lines. Fun question!
@oih82w8 said:
I am pretty sure that the REV Die is the anvil position and the OBV is the hammer. I have been wrong before. Perhaps @dcarr could enlighten us?
Traditionally, the reverse die is the anvil die. However, there are exceptions. The question is whether this is one of the exceptions.
Trivia question: How can you tell after the fact which die was the anvil die?
I've recently noticed SLH have better rims on the reverse than the obverse. Perhaps by wear patterns At least that appears to be the case with 1855/54 SLH. However, Barber halves usually wear into the reverse lettering and design before the obverse, so I'm not sure if this is related to being struck with the anvil die, or differences in die design and metal flow.
My other guess would be checking the rims or checking flow lines. Fun question!
The standard answer is to look at coins struck with partial collars. By definition, the hammer die moves, while the anvil die is fixed. The collar is nearly fixed, and associated with the anvil die. In a partial collar strike, the collar has shifted towards the anvil die somewhat. Therefore, on a partial collar strike the portion of the edge struck outside of the collar is the portion nearest the hammer die, while the portion within the collar is nearest the anvil die.
Heritage has sold several seated half dollars with partial collar strikes. It's hard to tell with face-on pics, but I'm pretty sure they were struck with obverse die as the hammer die.
@oih82w8 said:
I am pretty sure that the REV Die is the anvil position and the OBV is the hammer. I have been wrong before. Perhaps @dcarr could enlighten us?
Traditionally, the reverse die is the anvil die. However, there are exceptions. The question is whether this is one of the exceptions.
Trivia question: How can you tell after the fact which die was the anvil die?
I've recently noticed SLH have better rims on the reverse than the obverse. Perhaps by wear patterns At least that appears to be the case with 1855/54 SLH. However, Barber halves usually wear into the reverse lettering and design before the obverse, so I'm not sure if this is related to being struck with the anvil die, or differences in die design and metal flow.
My other guess would be checking the rims or checking flow lines. Fun question!
VF20 with a worn rim.
I had not noticed this. Without doing any research, I would guess that this is caused by the rim on the reverse hub being slightly stronger, though there could also be a slight difference in the curvature of the field on the hub.
Numismatist. 50 year member ANA. Winner of four ANA Heath Literary Awards; three Wayte and Olga Raymond Literary Awards; Numismatist of the Year Award 2009, and Lifetime Achievement Award 2020. Winner numerous NLG Literary Awards.
@oih82w8 said:
I am pretty sure that the REV Die is the anvil position and the OBV is the hammer. I have been wrong before. Perhaps @dcarr could enlighten us?
Traditionally, the reverse die is the anvil die. However, there are exceptions. The question is whether this is one of the exceptions.
Trivia question: How can you tell after the fact which die was the anvil die?
I've recently noticed SLH have better rims on the reverse than the obverse. Perhaps by wear patterns At least that appears to be the case with 1855/54 SLH. However, Barber halves usually wear into the reverse lettering and design before the obverse, so I'm not sure if this is related to being struck with the anvil die, or differences in die design and metal flow.
My other guess would be checking the rims or checking flow lines. Fun question!
The standard answer is to look at coins struck with partial collars. By definition, the hammer die moves, while the anvil die is fixed. The collar is nearly fixed, and associated with the anvil die. In a partial collar strike, the collar has shifted towards the anvil die somewhat. Therefore, on a partial collar strike the portion of the edge struck outside of the collar is the portion nearest the hammer die, while the portion within the collar is nearest the anvil die.
Heritage has sold several seated half dollars with partial collar strikes. It's hard to tell with face-on pics, but I'm pretty sure they were struck with obverse die as the hammer die.
Quite right.
While at ANACS I looked at a group of errors that had a 1921 Peace dollar that had a partial collar flange adjacent to the obverse, and a 1922(-?) Peace dollar with a partial collar flange adjacent to the reverse. I assume that they made the change as part of the effort to make the coins strike up better.
Numismatist. 50 year member ANA. Winner of four ANA Heath Literary Awards; three Wayte and Olga Raymond Literary Awards; Numismatist of the Year Award 2009, and Lifetime Achievement Award 2020. Winner numerous NLG Literary Awards.
@oih82w8 said:
I am pretty sure that the REV Die is the anvil position and the OBV is the hammer. I have been wrong before. Perhaps @dcarr could enlighten us?
Traditionally, the reverse die is the anvil die. However, there are exceptions. The question is whether this is one of the exceptions.
Trivia question: How can you tell after the fact which die was the anvil die?
I've recently noticed SLH have better rims on the reverse than the obverse. Perhaps by wear patterns At least that appears to be the case with 1855/54 SLH. However, Barber halves usually wear into the reverse lettering and design before the obverse, so I'm not sure if this is related to being struck with the anvil die, or differences in die design and metal flow.
My other guess would be checking the rims or checking flow lines. Fun question!
VF20 with a worn rim.
I had not noticed this. Without doing any research, I would guess that this is caused by the rim on the reverse hub being slightly stronger, though there could also be a slight difference in the curvature of the field on the hub.
It's very common for lower grade 55/54 overdates to have weak rims from 7K - 10K. One can see it in the higher grades as well. Note the smaller dentil size on the left side of the obverse.
One of the most incredible major mint errors I've seen. Seated half errors are rare for having anything beyond very minor errors, and to have a coin with another denomination's planchet struck and retained is mind blowing.
Still wondering where all the extra metal went when this coin was struck with enough pressure to completely indent a silver planchet into the field of another silver planchet while for the most part retaining the integrity of the former. Seems to me with that much extra metal between the dies [at obviously high pressure] that the features everywhere would be absolutely chiseled. Where did the metal go?
What is the weight of the half planchet without the retained half dime?
@tradedollarnut said:
Still wondering where all the extra metal went when this coin was struck with enough pressure to completely indent a silver planchet into the field of another silver planchet while for the most part retaining the integrity of the former. Seems to me with that much extra metal between the dies [at obviously high pressure] that the features everywhere would be absolutely chiseled. Where did the metal go?
What is the weight of the half planchet without the retained half dime?
The half dime indent is localized and not spread out over the whole coin. So the strike will be better opposite the indent. But the rest of the strike that is not bolstered by the indent will be average at best. The half dime planchet resting on the half dollar planchet would make it harder for the dies to fully reach the half dollar planchet. The stars opposite the indent are unusually well struck. But as soon as you move away from the indent area, the stars go weak.
@tradedollarnut said:
Still wondering where all the extra metal went when this coin was struck with enough pressure to completely indent a silver planchet into the field of another silver planchet while for the most part retaining the integrity of the former. Seems to me with that much extra metal between the dies [at obviously high pressure] that the features everywhere would be absolutely chiseled. Where did the metal go?
What is the weight of the half planchet without the retained half dime?
The half dime indent is localized and not spread out over the whole coin. So the strike will be better opposite the indent. But the rest of the strike that is not bolstered by the indent will be average at best. The half dime planchet resting on the half dollar planchet would make it harder for the dies to fully reach the half dollar planchet. The stars opposite the indent are unusually well struck. But as soon as you move away from the indent area, the stars go weak.
Okkkkk - you would think that the fact that the half dime planchet is indented to the same surface as the regular fields is proof that the metal had to flow outwards. Silver does NOT compress to any meaningful extent so the metal HAD to flow outward.
@tradedollarnut said:
Still wondering where all the extra metal went when this coin was struck with enough pressure to completely indent a silver planchet into the field of another silver planchet while for the most part retaining the integrity of the former. Seems to me with that much extra metal between the dies [at obviously high pressure] that the features everywhere would be absolutely chiseled. Where did the metal go?
What is the weight of the half planchet without the retained half dime?
The half dime indent is localized and not spread out over the whole coin. So the strike will be better opposite the indent. But the rest of the strike that is not bolstered by the indent will be average at best. The half dime planchet resting on the half dollar planchet would make it harder for the dies to fully reach the half dollar planchet. The stars opposite the indent are unusually well struck. But as soon as you move away from the indent area, the stars go weak.
Okkkkk - you would think that the fact that the half dime planchet is indented to the same surface as the regular fields is proof that the metal had to flow outwards. Silver does NOT compress to any meaningful extent so the metal HAD to flow outward.
Yes, but did you notice how well the arrows, talons, feathers and eagle shield are struck?
The half by itself is normal weight according to the link earlier in thread.
I don't know and I also don't know that much about the coin striking process. However, I will throw out some ummm stuff and see if anything sticks to the walls.
Not sure how to describe this but will give it a try.
Initially as the dies are coming together the half dime planchet is resting on the reverse die with the half dollar above (I am assuming the reverse is anvil but doesn't matter much). The half dime will get pressure from the fields first and then quickly fill the device area.
At this point the inner surface of the half dime kind of becomes the die to the half dollar planchet and is trying to put a dent into it. Since it is initially thicker under the half dime there could initially be more pressure there. Could this the cause the half dollar planchet under the half dime to flow the 'metal' outward toward about 4/5 o/c to 6/7 o/c rim? This is roughly where the half dime planchet is on the reverse. More pressure under this area so the half dollar 'metal' flows under the half dime more initially.
I notice the dentils in this area are full and is the rim any thicker? Also as noted the opposite/obverse side is well struck in this area.
As the dies come together and the pressure across the half dollar planchet becomes more traditionally even, then a more typical half dollar metal flow happens. However, if much of the half dollar planchet 'metal' has already moved or flowed outward as described above, then there might not be enough 'metal' remaining to flow and fill the stars towards the 3 o/c and 9 o/c positions.
The half dime is 10% of the weight of the half dollar. So can this be consumed but the rims, dentils, stars and devices under and adjacent to the half dime?
Like I said, I don't know but that is the thought I came up with looking at the true views.
https://youtube.com/watch?v=2YNufnS_kf4 - Mama I'm coming home ...................................................................................................................................................................... RLJ 1958 - 2023
The abilities of a regular production coin press to move metal around are not unlimited. That is why they upset the rims of blanks to turn them into easier to strike planchets. It is also why 19th century Proofs were struck two or more times on a different kind of coin press.
Numismatist. 50 year member ANA. Winner of four ANA Heath Literary Awards; three Wayte and Olga Raymond Literary Awards; Numismatist of the Year Award 2009, and Lifetime Achievement Award 2020. Winner numerous NLG Literary Awards.
@tradedollarnut said:
Still wondering where all the extra metal went when this coin was struck with enough pressure to completely indent a silver planchet into the field of another silver planchet while for the most part retaining the integrity of the former. Seems to me with that much extra metal between the dies [at obviously high pressure] that the features everywhere would be absolutely chiseled. Where did the metal go?
What is the weight of the half planchet without the retained half dime?
The half dime indent is localized and not spread out over the whole coin. So the strike will be better opposite the indent. But the rest of the strike that is not bolstered by the indent will be average at best. The half dime planchet resting on the half dollar planchet would make it harder for the dies to fully reach the half dollar planchet. The stars opposite the indent are unusually well struck. But as soon as you move away from the indent area, the stars go weak.
Okkkkk - you would think that the fact that the half dime planchet is indented to the same surface as the regular fields is proof that the metal had to flow outwards. Silver does NOT compress to any meaningful extent so the metal HAD to flow outward.
"Metal flow" is not really a term that I like to use, or think is accurate.
Metal doesn't really "flow". But it bends. When a planchet is struck, there is localized bending and shearing to form the design. It seems like a weird way of thinking about it (at first). "Flow" implies that atoms of metal in the planchet move a significant distance in relation to other metal atoms. That is not what happens (except in cases of shearing). When a specific atom has a strong force applied to it, that atom will pull and push on the atoms around it. All of the localized atoms will deform and displace together. But an atom will not jump ahead of the atom in front of it.
The half dime planchet did flatten out and increase in diameter. The half dollar planchet also increased in diameter during the strike, with the final diameter being limited by the collar. If the reeded-edge collar has an inner nominal diameter of 30.6mm, the half dollar planchet was likely about 30.4mm. That leaves about 0.1mm spacing between the planchet and collar (before the strike). The half dollar planchet would have a nominal thickness of about 1.8mm. The maximum radial expansion distance would be 0.1mm (near the rim). So the full effects on the strike from the half dime planchet would be limited to the indent area and diminish from there. At almost 2mm beyond the indent area the enhanced striking quality would be nonexistent (0.1mm + 1.8mm = 1.9mm).
So where did the extra metal go ?
The nominal thickness of the mated pair would have to be about 10% thicker than a normal half dollar. Metal in and around the indent area pushes on surrounding metal, and that surrounding metal pushes other metal outward towards the collar.
The extra thickness of the overlapping half dime planchet resists the movement of the die and keeps the dies from making full contact with the half dollar planchet in the areas away from the indent.
Also, people think that dies are perfectly rigid, especially in relation to the planchet. But they are not. Dies will flex to some degree (up to the limit where they crack). Note that steel used in springs is quite hard, like die steel. But in this instance the dies can not flex enough to overcome the localized thickness and obtain a full strike away from the indent.
@CaptHenway said:
Let me begin by saying that I absolutely love this pair! No question a legitimate major Mint error. I would be pleased and proud to own it.
And now, a major mystery. Look at the struck side of the Half Dime. Note the ring of peripheral toning near its circumference, typical of many a silver coin of the 19th Century.
On this Half Dime, much of the periphery is no where near the periphery of the half dollar. So how did those areas acquire peripheral toning?
TD
Slight difference in the alloy mix? Maybe the two pieces were stored separately? I think you would need to know something about how/where it has been for the previous 160 years to be able to give a comprehensive answer to that one.
Sean Reynolds
Every batch of silver is different. Trace impurities, the amount of work hardening imparted during the rolling and punching, and the temperature at which it was annealed, can all affect how the silver tones over time. So I am not surprised that the half dime would have toned differently than the half dollar.
The crescent toning of the half dime is possibly due to the two pieces being housed in separate holders for a long time.
On coins with planchets or struck coins struck into them, often there is localized strength opposite the planchet/coin, and sometimes no change or just moderate weakness around other areas of the coin. Smarter people know all "why" this happens, but I know it happens nevertheless.
On coins where a planchet is struck against another planchet of the same size (say a 50c against a 50c), unless an additional error was involved, you will always see some degree of finning around the rim where the metal was forced out between the collar and upper or lower die. These coins will virtually always be well struck.
Coins with a smaller planchet struck into them (especially on a coin like this with a tiny half dime size planchet, which is much smaller than the half dollar planchet), may have just minor change in strike sharpness/weakness. There doesn't seem to be enough metal on coins like that to make much of a difference in the striking characteristics on coins like that.
For comparing how the smaller planchet indents and fits into the larger one, here is a unique mated Franklin Half pair that I handled twice:
mikebyers.com Dealer in Major Mint Errors, Die Trials & Patterns - Author of NLG Best World Coin Book World's Greatest Mint Errors - Publisher & Editor of minterrornews.com.
The nominal thickness of the mated pair would have to be about 10% thicker than a normal half dollar. Metal in and around the indent area pushes on surrounding metal, and that surrounding metal pushes other metal outward towards the collar.
The extra thickness of the overlapping half dime planchet resists the movement of the die and keeps the dies from making full contact with the half dollar planchet in the areas away from the indent.
Also, people think that dies are perfectly rigid, especially in relation to the planchet. But they are not. Dies will flex to some >degree (up to the limit where they crack). Note that steel used in springs is quite hard, like die steel. But in this instance the >dies can not flex enough to overcome the localized thickness and obtain a full strike away from the indent.
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Thanks
I am still trying to picture this, kind of interesting. When looking that the TV I tried to simplify things and maybe that is not good. I picture the dies without considering curvature or upset rims, just flat dies and a flat planchet. I then pictured stopping the dies when the opposing field surfaces were the thickness of the half dollar planchet. So on a normal half dollar planchet this would be just before pressure is applied. Then with the inclusion of the half dime planchet I wondered where did this metal go as it is too thick in this area but still before applying pressure outside the half dime area.
My thought is that the half dime planchet has already been pushed/moved (didn't use flow ) into the reverse die device areas.
Noting the final half dime planchet is generally round and about the same diameter as a half dime so it didn't move outward that much.
Is my thinking already in error here?
Also as the half dime is being pressed into the half dollar planchet that the half dollar planchet might be moved to a lesser extent into the obverse devices and perhaps the half dollar is starting to push/move metal outward toward the rim. This making a little more room for the added half dime planchet.
Again picturing this before the actual full strike. I know it happens in a split second.
https://youtube.com/watch?v=2YNufnS_kf4 - Mama I'm coming home ...................................................................................................................................................................... RLJ 1958 - 2023
Good, it did. Another interesting aspect of "metal flow" in general is how the metal in the half dollar planchet immediately outside the border of the half dime planchet was pushed DOWN by the strike rather than being well struck up by the presence of all this extra metal. Note the top of the H and the inner ends of the leaves.
Numismatist. 50 year member ANA. Winner of four ANA Heath Literary Awards; three Wayte and Olga Raymond Literary Awards; Numismatist of the Year Award 2009, and Lifetime Achievement Award 2020. Winner numerous NLG Literary Awards.
@CaptHenway said:
Let me see if this picture works
Good, it did. Another interesting aspect of "metal flow" in general is how the metal in the half dollar planchet immediately outside the border of the half dime planchet was pushed DOWN by the strike rather than being well struck up by the presence of all this extra metal. Note the top of the H and the inner ends of the leaves.
That is an effect of my contention that metal "bends" rather than "flows".
Amazing this exists and survived- I will definitely check it out at FUN. Does the owner plan to sell or auction it? Seems like it should set some kind of error record price.
@dcarr If you have unlimited spare time (hah!) I'd love to see an experiment something along these lines:
1) Prepare a planchet with some sort of fine grid on both sides.
2) Take good clear "before" photos.
3) Strike that planchet with fairly plain dies (simple design, not much going on) in a way that the original grid is still visible after striking
4) Take good clear "after" photos.
5) Do a photo overlay showing how the original grid was distorted during the strike.
That should be a pretty compelling visualization of what metal flow "really" looks like.
Unfortunately I don't know how to do any of the important steps. My guess is that it would be tough to get a grid that was fine enough to be useful while also robust enough to be visible after the strike...
@CaptHenway said:
Let me see if this picture works
Good, it did. Another interesting aspect of "metal flow" in general is how the metal in the half dollar planchet immediately outside the border of the half dime planchet was pushed DOWN by the strike rather than being well struck up by the presence of all this extra metal. Note the top of the H and the inner ends of the leaves.
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I had noticed that also and the small amount of arrow tips on the opposite side appear similar. However, I noticed that at the top or the eagle, this is not present.
Then the dentils and rim below the half dime are quite full and wide but to each side of the half dime are weak. The dentils a the top of the half dollar also appear strong.
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https://youtube.com/watch?v=2YNufnS_kf4 - Mama I'm coming home ...................................................................................................................................................................... RLJ 1958 - 2023
I just don't get it. First is a screen shot of the half dime in the half dollar from the OP. At the top half the half dime fits snug and almost without a seem into the half dollar. On the right the half dime is rotated with respect to the arrow heads (and L in DOL and the dot) on the half dollar. Then on the bottom and bottom left where the letters (and other) are wrapped down into the edge, the half dime has a notable gap between it and the half dollar. As if the wrapped letters keep/kept it away (didn't fill the gap). Another enlarged shot of that.
EDIT:
I found this at NNP. I am wondering if 'die draw' could account for the misalignment of the arrow heads (and DOL dot) and maybe the gap at bottom and bottom left. As it is with the rotation the coin(s) would not fit into the die. So could this type of movement account for it.
"Metal flow stops at the instant the dies are fully extended and there is no more pressure. However, in rare instances, as the dies retract some metal may spring back somewhat (by MOLECULAR MEMORY) and cause DIE DRAW. This is cured in coining with a slightly stronger impression."
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https://youtube.com/watch?v=2YNufnS_kf4 - Mama I'm coming home ...................................................................................................................................................................... RLJ 1958 - 2023
@jonathanb said: @dcarr If you have unlimited spare time (hah!) I'd love to see an experiment something along these lines:
1) Prepare a planchet with some sort of fine grid on both sides.
2) Take good clear "before" photos.
3) Strike that planchet with fairly plain dies (simple design, not much going on) in a way that the original grid is still visible after striking
4) Take good clear "after" photos.
5) Do a photo overlay showing how the original grid was distorted during the strike.
That should be a pretty compelling visualization of what metal flow "really" looks like.
Unfortunately I don't know how to do any of the important steps. My guess is that it would be tough to get a grid that was fine enough to be useful while also robust enough to be visible after the strike...
I like this idea, but do more than one. Have one centered, one halfway to the edge and another right at the edge.
Numismatist. 50 year member ANA. Winner of four ANA Heath Literary Awards; three Wayte and Olga Raymond Literary Awards; Numismatist of the Year Award 2009, and Lifetime Achievement Award 2020. Winner numerous NLG Literary Awards.
@jonathanb said: @dcarr If you have unlimited spare time (hah!) I'd love to see an experiment something along these lines:
1) Prepare a planchet with some sort of fine grid on both sides.
2) Take good clear "before" photos.
3) Strike that planchet with fairly plain dies (simple design, not much going on) in a way that the original grid is still visible after striking
4) Take good clear "after" photos.
5) Do a photo overlay showing how the original grid was distorted during the strike.
That should be a pretty compelling visualization of what metal flow "really" looks like.
Unfortunately I don't know how to do any of the important steps. My guess is that it would be tough to get a grid that was fine enough to be useful while also robust enough to be visible after the strike...
If I have some time (don't know when) I might try that.
For now, you could potentially look at adjustment marks on early US coins to see how they distort (or don't distort).
@jonathanb said: @dcarr If you have unlimited spare time (hah!) I'd love to see an experiment something along these lines:
1) Prepare a planchet with some sort of fine grid on both sides.
2) Take good clear "before" photos.
3) Strike that planchet with fairly plain dies (simple design, not much going on) in a way that the original grid is still visible after striking
4) Take good clear "after" photos.
5) Do a photo overlay showing how the original grid was distorted during the strike.
That should be a pretty compelling visualization of what metal flow "really" looks like.
Unfortunately I don't know how to do any of the important steps. My guess is that it would be tough to get a grid that was fine enough to be useful while also robust enough to be visible after the strike...
If I have some time (don't know when) I might try that.
For now, you could potentially look at adjustment marks on early US coins to see how they distort (or don't distort).
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That is what I was just thinking and looking at. Did a thread with some. Often the ones in the field get 'stamped' out but there are many examples with them going from device to field. They appear to remain straight. But this is not an overlay with more precision. Also there are roller marks. A little tougher to find 'long' ones (for me) but do recall some Morgans (I believe O mints) that had them almost across the coin. They also appear to remain straight. There are numerous short examples of them on Morgans on Liberty jaw, ear + hair and again straight.
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EDIT: @jonathanb I probably should have included links in initial post. Here is my thread and another that has several more examples posted down in the body of the thread. As noted they appear straight but yes could be some slight movement not easily seen.
@CaptHenway Don't recall the shiny shadows but not something I would be looking for. It reminds me of pull away toning and having read that that is due to the metal stress or movement or similar (don't recall the wording). Here is one I just located the has some shadow but not shiny (click to enlarge).
Hope the link works (no preview on EDIT) as I don't recall using this type link (they used to auto download) but if it doesn't, then can go to this TV page below and select the obverse and download.
If prestrike marks remain straight after the strike, that implies that the only metal movement is "vertical" relative to a plane through the center of the coin, not "horizontal". That also implies that the density of the fields is higher that the density of the struck devices, since the moving metal has to go somewhere.
That doesn't sound right to me. I'd sooner guess that the amount of horizontal movement is small, and hard to see relative to the scale of the adjustment marks or roller marks.
Unfortunately, if that's true it might be hard to see the horizontal movement from a controlled experiment also.
Just to carry on the discussion of "metal flow" in general, who has a nice picture of one of those SF dollars from the early 1880's with the shiny shadows on the outsides of the stars/letters/date? I believe that that is caused by the radial movement of metal into and back out of the recessed stars/letters/date, changing the molecular structure as it goes.
Numismatist. 50 year member ANA. Winner of four ANA Heath Literary Awards; three Wayte and Olga Raymond Literary Awards; Numismatist of the Year Award 2009, and Lifetime Achievement Award 2020. Winner numerous NLG Literary Awards.
I would love to know how the appearance of the rim on either side of a clipped planchet plays into the "flowing vs bending" conversation. The image below shows similar clips before and after the strike, I have always assumed the tapered rim was due to metal flowing between the dies into the void created by the clip.
Sean Reynolds
Incomplete planchets wanted, especially Lincoln Cents & type coins.
"Keep in mind that most of what passes as numismatic information is no more than tested opinion at best, and marketing blather at worst. However, I try to choose my words carefully, since I know that you guys are always watching." - Joe O'Connor
Sean, You may be on to something here. Notice how the upset rim tapers outwards into the Blakesley Effect.
Numismatist. 50 year member ANA. Winner of four ANA Heath Literary Awards; three Wayte and Olga Raymond Literary Awards; Numismatist of the Year Award 2009, and Lifetime Achievement Award 2020. Winner numerous NLG Literary Awards.
@jonathanb said:
If prestrike marks remain straight after the strike, that implies that the only metal movement is "vertical" relative to a plane through the center of the coin, not "horizontal". That also implies that the density of the fields is higher that the density of the struck devices, since the moving metal has to go somewhere.
That doesn't sound right to me. I'd sooner guess that the amount of horizontal movement is small, and hard to see relative to the scale of the adjustment marks or roller marks.
Unfortunately, if that's true it might be hard to see the horizontal movement from a controlled experiment also.
It should be mostly vertical for coins struck in a collar. Horizontal movement is constrained. I think the only place it could move (significantly) horizontally is into the devices.
@seanq said:
I would love to know how the appearance of the rim on either side of a clipped planchet plays into the "flowing vs bending" conversation. The image below shows similar clips before and after the strike, I have always assumed the tapered rim was due to metal flowing between the dies into the void created by the clip.
Sean Reynolds
That's because it can as it is no longer constrained by the collar along that axis.
Put a dime planchet into a half dollar collar and you get significant spread because there's no collar to constrain it.
@seanq said:
I would love to know how the appearance of the rim on either side of a clipped planchet plays into the "flowing vs bending" conversation. The image below shows similar clips before and after the strike, I have always assumed the tapered rim was due to metal flowing between the dies into the void created by the clip.
Sean Reynolds
That's because it can as it is no longer constrained by the collar along that axis.
Put a dime planchet into a half dollar collar and you get significant spread because there's no collar to constrain it.
By the same token, put a half dime planchet on top of a half dollar planchet and there is nothing to restrain it either. That would have a big influence on what the interface between the smaller and larger planchet looks like.
Sean Reynolds
Incomplete planchets wanted, especially Lincoln Cents & type coins.
"Keep in mind that most of what passes as numismatic information is no more than tested opinion at best, and marketing blather at worst. However, I try to choose my words carefully, since I know that you guys are always watching." - Joe O'Connor
@seanq said:
I would love to know how the appearance of the rim on either side of a clipped planchet plays into the "flowing vs bending" conversation. The image below shows similar clips before and after the strike, I have always assumed the tapered rim was due to metal flowing between the dies into the void created by the clip.
Sean Reynolds
That's because it can as it is no longer constrained by the collar along that axis.
Put a dime planchet into a half dollar collar and you get significant spread because there's no collar to constrain it.
By the same token, put a half dime planchet on top of a half dollar planchet and there is nothing to restrain it either. That would have a big influence on what the interface between the smaller and larger planchet looks like.
Sean Reynolds
Quite likely. The half dime has clearly spread laterally.
@Twohawks1 said:
I will have this mated pair at my table at the FUN show this Jan. Our table is in the same isle as PCGS. Heritage Coins & Collectibles if anyone wishes to see them in person.
Thought I saw a sign at the FUN table saying not for sale?
Comments
Just stunning!!
Disclaimer: I'm not a dealer, trader, grader, investor or professional numismatist. I'm just a hobbyist. (To protect me but mostly you! 🤣 )
Proof that not all the good stuff has been graded. There is plenty out there to be found.
Paper money eventually returns to its intrinsic value. Zero. Voltaire. Ebay coinbowlllc
Obviously the Half Dime planchet spread some as it tried to fit into the Half Dollar planchet during this abnormal strike. However, IMHO there is little or no normal outwards expansion in the center of a coin during a normal strike of a coin with raised central devices on one or both sides.
This is based upon my study of the 1922-D cent dies, many of which were severely overused. There are many reverse dies in very late die states where the wheat ears and the legend E PLURIBUS UNUM are greatly degraded via outward expansion die flow, as well as the letters of UNITED STATES OF AMERICA closest to the wheat ears. However,these dies are often still near normal in their centers. I believe that this is caused by the metal in the center of the planchet moving up into the central device of the hammer die and down into the central device or lettering of the anvil die, rather than outwards into the rim.
It was in the Heritage Auctions 2024 Platinum FUN ‘Auction Previews’ but was removed…
Good to know. Sometimes there can be good reasons to remove something from an auction. I wonder what it was here.
That makes sense. And the fact that the half dime planchet was not elongated in striking tends to back you up.
BTW, have you noticed the darkish patch on the center of the obverse? It pretty much matches up to the darker areas on the reverse. Now I'm really confused...
Doggedly collecting coins of the Central American Republic.
Visit the Society of US Pattern Collectors at USPatterns.com.
A coin press could operate with the dies either way.
Typically, as the last step in the stamping cycle, the lower (anvil) die pushes the struck coin out of the collar.
A careful examination of a coin's edge can reveal which direction the ejection "slide marks" go, and that can infer the orientation of the dies.
Totally agree. Stunning !
I've recently noticed SLH have better rims on the reverse than the obverse. Perhaps by wear patterns At least that appears to be the case with 1855/54 SLH. However, Barber halves usually wear into the reverse lettering and design before the obverse, so I'm not sure if this is related to being struck with the anvil die, or differences in die design and metal flow.
My other guess would be checking the rims or checking flow lines. Fun question!
VF20 with a worn rim.
Thanks, @dcarr. I learned something new. I love this board.
The standard answer is to look at coins struck with partial collars. By definition, the hammer die moves, while the anvil die is fixed. The collar is nearly fixed, and associated with the anvil die. In a partial collar strike, the collar has shifted towards the anvil die somewhat. Therefore, on a partial collar strike the portion of the edge struck outside of the collar is the portion nearest the hammer die, while the portion within the collar is nearest the anvil die.
Heritage has sold several seated half dollars with partial collar strikes. It's hard to tell with face-on pics, but I'm pretty sure they were struck with obverse die as the hammer die.
So why do cuds form along the reverse, or are they simply chips to the collar die?
I had not noticed this. Without doing any research, I would guess that this is caused by the rim on the reverse hub being slightly stronger, though there could also be a slight difference in the curvature of the field on the hub.
Quite right.
While at ANACS I looked at a group of errors that had a 1921 Peace dollar that had a partial collar flange adjacent to the obverse, and a 1922(-?) Peace dollar with a partial collar flange adjacent to the reverse. I assume that they made the change as part of the effort to make the coins strike up better.
It's very common for lower grade 55/54 overdates to have weak rims from 7K - 10K. One can see it in the higher grades as well. Note the smaller dentil size on the left side of the obverse.
All that extra metal and the stars, mottos and liberty’s foot still aren’t struck up. Interesting
One of the most incredible major mint errors I've seen. Seated half errors are rare for having anything beyond very minor errors, and to have a coin with another denomination's planchet struck and retained is mind blowing.
Still wondering where all the extra metal went when this coin was struck with enough pressure to completely indent a silver planchet into the field of another silver planchet while for the most part retaining the integrity of the former. Seems to me with that much extra metal between the dies [at obviously high pressure] that the features everywhere would be absolutely chiseled. Where did the metal go?
What is the weight of the half planchet without the retained half dime?
The half dime indent is localized and not spread out over the whole coin. So the strike will be better opposite the indent. But the rest of the strike that is not bolstered by the indent will be average at best. The half dime planchet resting on the half dollar planchet would make it harder for the dies to fully reach the half dollar planchet. The stars opposite the indent are unusually well struck. But as soon as you move away from the indent area, the stars go weak.
Okkkkk - you would think that the fact that the half dime planchet is indented to the same surface as the regular fields is proof that the metal had to flow outwards. Silver does NOT compress to any meaningful extent so the metal HAD to flow outward.
Yes, but did you notice how well the arrows, talons, feathers and eagle shield are struck?
The half by itself is normal weight according to the link earlier in thread.
Interesting on where the 'metal' went.
I don't know and I also don't know that much about the coin striking process. However, I will throw out some ummm stuff and see if anything sticks to the walls.
Not sure how to describe this but will give it a try.
Initially as the dies are coming together the half dime planchet is resting on the reverse die with the half dollar above (I am assuming the reverse is anvil but doesn't matter much). The half dime will get pressure from the fields first and then quickly fill the device area.
At this point the inner surface of the half dime kind of becomes the die to the half dollar planchet and is trying to put a dent into it. Since it is initially thicker under the half dime there could initially be more pressure there. Could this the cause the half dollar planchet under the half dime to flow the 'metal' outward toward about 4/5 o/c to 6/7 o/c rim? This is roughly where the half dime planchet is on the reverse. More pressure under this area so the half dollar 'metal' flows under the half dime more initially.
I notice the dentils in this area are full and is the rim any thicker? Also as noted the opposite/obverse side is well struck in this area.
As the dies come together and the pressure across the half dollar planchet becomes more traditionally even, then a more typical half dollar metal flow happens. However, if much of the half dollar planchet 'metal' has already moved or flowed outward as described above, then there might not be enough 'metal' remaining to flow and fill the stars towards the 3 o/c and 9 o/c positions.
The half dime is 10% of the weight of the half dollar. So can this be consumed but the rims, dentils, stars and devices under and adjacent to the half dime?
Like I said, I don't know but that is the thought I came up with looking at the true views.
https://youtube.com/watch?v=2YNufnS_kf4 - Mama I'm coming home ...................................................................................................................................................................... RLJ 1958 - 2023
The abilities of a regular production coin press to move metal around are not unlimited. That is why they upset the rims of blanks to turn them into easier to strike planchets. It is also why 19th century Proofs were struck two or more times on a different kind of coin press.
"Metal flow" is not really a term that I like to use, or think is accurate.
Metal doesn't really "flow". But it bends. When a planchet is struck, there is localized bending and shearing to form the design. It seems like a weird way of thinking about it (at first). "Flow" implies that atoms of metal in the planchet move a significant distance in relation to other metal atoms. That is not what happens (except in cases of shearing). When a specific atom has a strong force applied to it, that atom will pull and push on the atoms around it. All of the localized atoms will deform and displace together. But an atom will not jump ahead of the atom in front of it.
The half dime planchet did flatten out and increase in diameter. The half dollar planchet also increased in diameter during the strike, with the final diameter being limited by the collar. If the reeded-edge collar has an inner nominal diameter of 30.6mm, the half dollar planchet was likely about 30.4mm. That leaves about 0.1mm spacing between the planchet and collar (before the strike). The half dollar planchet would have a nominal thickness of about 1.8mm. The maximum radial expansion distance would be 0.1mm (near the rim). So the full effects on the strike from the half dime planchet would be limited to the indent area and diminish from there. At almost 2mm beyond the indent area the enhanced striking quality would be nonexistent (0.1mm + 1.8mm = 1.9mm).
So where did the extra metal go ?
The nominal thickness of the mated pair would have to be about 10% thicker than a normal half dollar. Metal in and around the indent area pushes on surrounding metal, and that surrounding metal pushes other metal outward towards the collar.
The extra thickness of the overlapping half dime planchet resists the movement of the die and keeps the dies from making full contact with the half dollar planchet in the areas away from the indent.
Also, people think that dies are perfectly rigid, especially in relation to the planchet. But they are not. Dies will flex to some degree (up to the limit where they crack). Note that steel used in springs is quite hard, like die steel. But in this instance the dies can not flex enough to overcome the localized thickness and obtain a full strike away from the indent.
Every batch of silver is different. Trace impurities, the amount of work hardening imparted during the rolling and punching, and the temperature at which it was annealed, can all affect how the silver tones over time. So I am not surprised that the half dime would have toned differently than the half dollar.
The crescent toning of the half dime is possibly due to the two pieces being housed in separate holders for a long time.
On coins with planchets or struck coins struck into them, often there is localized strength opposite the planchet/coin, and sometimes no change or just moderate weakness around other areas of the coin. Smarter people know all "why" this happens, but I know it happens nevertheless.
On coins where a planchet is struck against another planchet of the same size (say a 50c against a 50c), unless an additional error was involved, you will always see some degree of finning around the rim where the metal was forced out between the collar and upper or lower die. These coins will virtually always be well struck.
Coins with a smaller planchet struck into them (especially on a coin like this with a tiny half dime size planchet, which is much smaller than the half dollar planchet), may have just minor change in strike sharpness/weakness. There doesn't seem to be enough metal on coins like that to make much of a difference in the striking characteristics on coins like that.
For comparing how the smaller planchet indents and fits into the larger one, here is a unique mated Franklin Half pair that I handled twice:
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Thanks
I am still trying to picture this, kind of interesting. When looking that the TV I tried to simplify things and maybe that is not good. I picture the dies without considering curvature or upset rims, just flat dies and a flat planchet. I then pictured stopping the dies when the opposing field surfaces were the thickness of the half dollar planchet. So on a normal half dollar planchet this would be just before pressure is applied. Then with the inclusion of the half dime planchet I wondered where did this metal go as it is too thick in this area but still before applying pressure outside the half dime area.
My thought is that the half dime planchet has already been pushed/moved (didn't use flow
) into the reverse die device areas.
Noting the final half dime planchet is generally round and about the same diameter as a half dime so it didn't move outward that much.
Is my thinking already in error here?
Also as the half dime is being pressed into the half dollar planchet that the half dollar planchet might be moved to a lesser extent into the obverse devices and perhaps the half dollar is starting to push/move metal outward toward the rim. This making a little more room for the added half dime planchet.
Again picturing this before the actual full strike. I know it happens in a split second.
https://youtube.com/watch?v=2YNufnS_kf4 - Mama I'm coming home ...................................................................................................................................................................... RLJ 1958 - 2023
Let me see if this picture works
Good, it did. Another interesting aspect of "metal flow" in general is how the metal in the half dollar planchet immediately outside the border of the half dime planchet was pushed DOWN by the strike rather than being well struck up by the presence of all this extra metal. Note the top of the H and the inner ends of the leaves.
That is an effect of my contention that metal "bends" rather than "flows".
Amazing this exists and survived- I will definitely check it out at FUN. Does the owner plan to sell or auction it? Seems like it should set some kind of error record price.
@dcarr If you have unlimited spare time (hah!) I'd love to see an experiment something along these lines:
1) Prepare a planchet with some sort of fine grid on both sides.
2) Take good clear "before" photos.
3) Strike that planchet with fairly plain dies (simple design, not much going on) in a way that the original grid is still visible after striking
4) Take good clear "after" photos.
5) Do a photo overlay showing how the original grid was distorted during the strike.
That should be a pretty compelling visualization of what metal flow "really" looks like.
Unfortunately I don't know how to do any of the important steps. My guess is that it would be tough to get a grid that was fine enough to be useful while also robust enough to be visible after the strike...
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I had noticed that also and the small amount of arrow tips on the opposite side appear similar. However, I noticed that at the top or the eagle, this is not present.
Then the dentils and rim below the half dime are quite full and wide but to each side of the half dime are weak. The dentils a the top of the half dollar also appear strong.
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https://youtube.com/watch?v=2YNufnS_kf4 - Mama I'm coming home ...................................................................................................................................................................... RLJ 1958 - 2023
I just don't get it. First is a screen shot of the half dime in the half dollar from the OP. At the top half the half dime fits snug and almost without a seem into the half dollar. On the right the half dime is rotated with respect to the arrow heads (and L in DOL and the dot) on the half dollar. Then on the bottom and bottom left where the letters (and other) are wrapped down into the edge, the half dime has a notable gap between it and the half dollar. As if the wrapped letters keep/kept it away (didn't fill the gap). Another enlarged shot of that.
EDIT:
I found this at NNP. I am wondering if 'die draw' could account for the misalignment of the arrow heads (and DOL dot) and maybe the gap at bottom and bottom left. As it is with the rotation the coin(s) would not fit into the die. So could this type of movement account for it.
"Metal flow stops at the instant the dies are fully extended and there is no more pressure. However, in rare instances, as the dies retract some metal may spring back somewhat (by MOLECULAR MEMORY) and cause DIE DRAW. This is cured in coining with a slightly stronger impression."
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https://youtube.com/watch?v=2YNufnS_kf4 - Mama I'm coming home ...................................................................................................................................................................... RLJ 1958 - 2023
I like this idea, but do more than one. Have one centered, one halfway to the edge and another right at the edge.
If I have some time (don't know when) I might try that.
For now, you could potentially look at adjustment marks on early US coins to see how they distort (or don't distort).
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That is what I was just thinking and looking at. Did a thread with some. Often the ones in the field get 'stamped' out but there are many examples with them going from device to field. They appear to remain straight. But this is not an overlay with more precision. Also there are roller marks. A little tougher to find 'long' ones (for me) but do recall some Morgans (I believe O mints) that had them almost across the coin. They also appear to remain straight. There are numerous short examples of them on Morgans on Liberty jaw, ear + hair and again straight.
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EDIT:
@jonathanb I probably should have included links in initial post. Here is my thread and another that has several more examples posted down in the body of the thread. As noted they appear straight but yes could be some slight movement not easily seen.
https://forums.collectors.com/discussion/1075564/that-had-to-hurt
https://forums.collectors.com/discussion/1013651/adjustment-marks-on-capped-bust-halves
@CaptHenway Don't recall the shiny shadows but not something I would be looking for. It reminds me of pull away toning and having read that that is due to the metal stress or movement or similar (don't recall the wording). Here is one I just located the has some shadow but not shiny (click to enlarge).
Hope the link works (no preview on EDIT) as I don't recall using this type link (they used to auto download) but if it doesn't, then can go to this TV page below and select the obverse and download.
https://d1htnxwo4o0jhw.cloudfront.net/pcgs/cert/38460559/172379472.jpg
https://images.pcgs.com/trueview/38460559
https://youtube.com/watch?v=2YNufnS_kf4 - Mama I'm coming home ...................................................................................................................................................................... RLJ 1958 - 2023
If prestrike marks remain straight after the strike, that implies that the only metal movement is "vertical" relative to a plane through the center of the coin, not "horizontal". That also implies that the density of the fields is higher that the density of the struck devices, since the moving metal has to go somewhere.
That doesn't sound right to me. I'd sooner guess that the amount of horizontal movement is small, and hard to see relative to the scale of the adjustment marks or roller marks.
Unfortunately, if that's true it might be hard to see the horizontal movement from a controlled experiment also.
Just to carry on the discussion of "metal flow" in general, who has a nice picture of one of those SF dollars from the early 1880's with the shiny shadows on the outsides of the stars/letters/date? I believe that that is caused by the radial movement of metal into and back out of the recessed stars/letters/date, changing the molecular structure as it goes.
Is it an inside job by an outsider, or an outside job by an insider ?
I would love to know how the appearance of the rim on either side of a clipped planchet plays into the "flowing vs bending" conversation. The image below shows similar clips before and after the strike, I have always assumed the tapered rim was due to metal flowing between the dies into the void created by the clip.
Sean Reynolds
"Keep in mind that most of what passes as numismatic information is no more than tested opinion at best, and marketing blather at worst. However, I try to choose my words carefully, since I know that you guys are always watching." - Joe O'Connor
Hmmmmmmm.........
Sean, You may be on to something here. Notice how the upset rim tapers outwards into the Blakesley Effect.
It should be mostly vertical for coins struck in a collar. Horizontal movement is constrained. I think the only place it could move (significantly) horizontally is into the devices.
That's because it can as it is no longer constrained by the collar along that axis.
Put a dime planchet into a half dollar collar and you get significant spread because there's no collar to constrain it.
By the same token, put a half dime planchet on top of a half dollar planchet and there is nothing to restrain it either. That would have a big influence on what the interface between the smaller and larger planchet looks like.
Sean Reynolds
"Keep in mind that most of what passes as numismatic information is no more than tested opinion at best, and marketing blather at worst. However, I try to choose my words carefully, since I know that you guys are always watching." - Joe O'Connor
Quite likely. The half dime has clearly spread laterally.
Here's another smaller planchet annular indent.
I am looking for its mate:
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Thought I saw a sign at the FUN table saying not for sale?
https://www.ebay.com/itm/355495528313