Franklin Proof Ghost image "error" SOLVED
Intueor
Posts: 310 ✭✭✭✭
Hi, need some expertize.
Below are images of a 1962 Proof Franklin with some dramatic Machine Doubling. When I first examined this piece without magnification, my immediate response was to consider making an appointment with the optometrist for a new eyeglass prescription, again 
. What is curious is the “ghost” outline on some of the devices. The “ghost” seems always to be in the direction of the spread. I have seen this anomaly on other proofs but am at a loss to explain what mechanism creates this shadow effect. Others have alluded to this curiosity but I do not recall an explanation. This is not an artifact of lighting; it is physically observable on the coin. I know it has no value but a clarification of the origin would contribute to my understanding of the minting process. Would anyone care to offer an explanation or opinion?
Thanks.
Comments
Valid question, I have not seen an explanation for this phenomena.....Perhaps @CaptHenway or @FredWeinberg may have the answer... Cheers, RickO
I've seen this characteristic on many proof coins. I was told that Proofs are struck twice and what you see in the field to the right is a prior strike and not associated with the ejection shift.
nice photos
we will find out when Fred arrives
Proofs of this period were struck once on a medal press.
The shapes noted by arrows do not fully match the adjacent digit or letter.
This might sound silly, but was a check made against reflections from the holder?
The reflection comment It is silly.
As I posted before, under high magnification, there is a definite under strike with the "outline" being into and part of the surface of the struck coin. I sure wish I had an electron microscope image to post.
Anyway, I respect your research about the number of strikes used to make proofs of this era even though it goes against everything I was ever told/read over the years!
The only other thing I can imagine is it is some form of unusual die wear That occurs ONLY on proofs but I don't buy it.
Thank you for taking the time to respond. The pictured coin is raw and the "ghost" is not a lighting or lens artifact. I double checked.
"Struck twice" is a logical and intuitive explanation. RogerB is right, the shapes noted by arrows do not fully match the adjacent digit or letter. On the image below, I have marked up the “offset” distance. The black arrows represent the MD offset. The red arrows represent the ghost image offset. What has me puzzled is that the gap in the MD doubling offset should be equidistant to the ghost image offset distance. Yet, the offsets are not equal? (Rather reminds me of “balloon” font.) This factor may place some doubt into the “second strike” theory. It is almost as if, when the coin was violently ejected from the collar, it was tilted and “slapped” upwards against the obverse die creating the partial ghost image in the direction of the MD shift. This "slapping" phenomenon, as you pointed out, would be independent of the actual MD effect. The curious thing about this is I have never observed the “ghost” effect on the reverse of a Proof coin. With a coin press running at tons of pressure, there must be an infinite number of output variations that can be generated.
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Thanks! icoopie
that's l not i
RE: "Struck twice" is a logical and intuitive explanation.
No, because that is not how proofs were made at that time. It might be "intuitively speculative" but it is neither logical not mechanically possible for the coin illustrated. Silver alloy work hardens on coining and a second blow, out of registration with the first, would leave a very prominent double image.
Yes, you are correct. A shift during multiple strikes would result in Strike Doubling but we all agree this coin has Machine Doubling.
OK, let us agree the number of times 1950-1963 proof Franklin coins were struck is a topic for another post. @#Insider2 and I only mentioned the multi-strike scenario because it was the “easy” answer but none of us believes it to be the correct answer. As astutely pointed out, the ghosts “do not fully match the adjacent digit or letter”. This can be extrapolated from the images.
My thoughts:
Somehow, the forces generated during the striking/ejection process caused that coin to slam against the surface of the retracting obverse die. Could it be a “timing” error during the retraction of the obverse die and/or a twist of the collar during ejection? Bear in mind the tons of pressure, The encased reeding and reverse devices would manifest significant torque from a twisting collar. Might this force reasonably cause the coin to “pop” out of the collar prematurely and be propelled upward toward the slightly retracting obverse die?
Any other ideas?
PS. While not pictured, the reverse of this proof is normal and shows no MD or "ghosts".
Don't put words into my mouth, I don't agree LOL... I've posted my opinion, and I'm sticking to it until I'm convinced I was fed a load of BS for some folks who should know.
The machine doubling on your coin has nothing to do with the offset "ghost" image "INTO" the coin's surface. I never paid any attention to these Proofs to see if any of them are ALSO machined doubled. IMO, Proofs with the "ghost" image ARE NOT rare - although they may be uncommon. I'll look for some of my Proofs next week.
FWIW, I once had a SMS half dollar that was struck through a very curly hair---twice! The hair moved between impressions, and the totally random pattern was indented into the coin in two different places.
On the very first image, The "Y," note how the tiny random flaws in the field of the die (a dot, two parallel vertical lines, etc.) appear both in the field and on the shelf. This is on the other side of the letter from the ghosting, but I just thought I would point it out.
That's impossible. We all know now that these coins were ONLY STRUCK ONCE!
I've found nothing that gives details on how 1965-1967 SMS coins were manufactured, But, I have not really looked either. The 1965 and 66 coins I've seen do not look like medal press products to me. Don't remember about 1967s. The mint was also experimenting with new design presses, and we know that by 1970 proofs got two blows in very rapid succession on an early Schuler model MRV press specifically designed to do this.
I've wondered about this too. Here's one that I came across. All of the lettering displays this "doubling," but look at the second "E" in "DEUTSCHES" for an especially extreme example.
Gobrecht's Engraved Mature Head Large Cent Model
https://www.instagram.com/rexrarities/?hl=en
So it sounds like during the "early years" a 1936 Proof half dollar was struck once but in 1974 a Proof half dollar MAY have been struck twice. That is the only way the "experts" who were still alive decades ago could have taught that Proofs are struck twice. They did not consider or were uninformed about anything before the 1970's.
Have you seen records that 1936-1940's and 1950's on early proofs were struck once. I have your book but have not read it yet so a Yes it is in my book will suffice...
Any records of how many blows for 19th Century proofs? It is a real shame all this two-strikes-for-Proofs misinformation has been spread for decades until you discovered the truth.
As I understand the "2-strike" hypothesis, the original suggestion applied to very early master coins that have clear evidence of more than one blow from a press. Somehow, that got elided into "all proofs were struck twice." Hence a lot of confusion.
Here is confirmation of using 2 strikes dating from 1973. There is a lot of useful information in these pages.
On Rexford's coin notice that like the OP's Franklin, the ghosts are not in alignment with adjacent characters and also not with one another. Compare "3" in the denomination with "9" in the date and "MAR" of mark.
RE: Have you seen records that 1936-1940's and 1950's on early proofs were struck once. I have your book but have not read it yet so a Yes it is in my book will suffice...
Any records of how many blows for 19th Century proofs? It is a real shame all this two-strikes-for-Proofs misinformation has been spread for decades until you discovered the truth.
Some of Dir Ross letters and those of Sinnock imply one blow, and there is no mention anywhere of more than one. The equipment could not reliably align low relief coins for two strikes.
Much the same for 19th century from about 1850 (and earlier, too) no mention of anything except a single blow but always from a medal press. Also no mechanical capability to do aligned strikes in normal operation and no mention of double struck proofs anywhere.
A large screw press was subject to too many mechanical and physical variables for low relief coin production. Early 19th century coins often show die chatter and bounce, but trying to do that deliberately and in perfect alignment would have been very difficult except on an occasional piece basis. It would be nice to have explicit notes from the Coiner (and later, Medal Clerk) but those are probably dust now.
Keen observation @RogerB. Also look at the rim devices of @Rexford MARK coin. They are also not aligned and there are anomalies in the reeding.
Great post Roger! Positively in
with the letter and your research. BTW, Dr. Goldman and Howard Johnson were involved with the "Omega" Counterfeits at the Mint Lab.
I've been holding something back to use in our discussion as I know for a fact that Mr. Johnson was just one of the folks who told my mentor that Proofs were struck twice! I never heard anything about the work being done on a medal press either! It appears that EVERYONE involved believed that was the case for all proofs including those made before 1970.
Therefore, until some researcher I respect - such as you - provides absolute "proof" (pun intended), I will consider what I learned directly from the guys making our coins and the researchers who came before both of us as true: PROOFS WERE STRUCK TWICE on specially prepared planchets.
While it is fascinating to debate on just when multiple strike proofs were introduced, it is still unclear if multiple strikes are the issue with the topic of ghost images.
Below are a set of images that further differentiate the Machine Doubling and the ghost image.
These images help to show the “gaps” between the MD rotation and the Ghost image. The differential is enlightening.
In the hope of hearing additional ideas on the ghost image topic, I submit the following hypothesis:
I did some internet research on torque calculations.
If the hammer obverse die were engaged at 75,000 pounds of pressure, the clockwise twist of 1.5 millimeters in a loose obverse die would generate 500 Newton-Meters or 368 ft/lbs of torque. The average force exerted on the bullet is 304 Newton-Meters or 224 ft/lbs of torque.
With this in mind, as the hammer die is raised from the coin after the strike, 368 ft/lbs of torque would seem sufficient force for the coin to “pop” out of the collar. Since the resistances in the collar and reverse die varies, the coin most likely would be propelled at an angle, strike the obverse die, and “grip” at the sharp edge of the incused design feature, in this case, the “2“. The point of initial impact, depth, and shift rotation degree of the ghost image are subject to torque forces in the direction of the MD. A secondary effect of torque is precession or “wobble”. (Spin a coin on a hard surface to see the interaction of torque and precession). As the impact wobble travels along the plain of the obverse die surface, less dramatic device ghosts are imparted by the incused device edges until the strength of the upward force gradually dissipates and no additional “gripping” occurs. Thus, no further ghosts appear in the remaining devices. This all happens within nanoseconds.
Examining the 1962 Proof coin seems to support the above hypothesis. The variation and spread in the ghost image do not convincingly seem to support the multiple strike scenario. The spread and definition of the ghost image diminish with distance from the “2” point of impact. Note the ghost spread on the “Y” vs the ghost spread on the “2”.
As to @Rexford posted MARK coin, I think it is also possible that this ghost image can occur on regular circulation strike MD’s if enough pressure is applied to the hammer obverse die and the planchet has a slightly polished surface. The MARK coin may show the effects of torque created by a shift in the collar instead of the hammer die. In this case, when the collar retracted, the precession occurred in the 360º circumference along the obverse die plain. This would explain why the ghost image is misaligned in different directions. This is just a “best guess” since I have no idea how a 1923 MARK was minted but the rims appear to show rotation pressure fissures.
I am sure some readers are thinking, “Who cares?” since no value is placed on this type of irregularity. However, there is no other site in the net-world where this type of discussion can occur. The ghost image is a re-occurring anomaly and a plausible explanation would solve a “mystery” or maybe someone already knows the answer.
The 1923 3 Mark is a proof, just to clear that up.
Gobrecht's Engraved Mature Head Large Cent Model
https://www.instagram.com/rexrarities/?hl=en
IMO, this discussion is getting off track. Die shifts are relatively common on all our coins. While it may turn out that the "ghosting" is related to some "mechanical" defect rather than a double strike, I hope we continue to focus on the "ghosting."
While looking for that characteristic today, about 30% of the Proofs I've examined show "ejection doubling.'' SEE BELOW:
Unfortunately, it is also evident on the OP's coin and has affected this discussion. So let's stay focused and forget about that in this thread as it is common. Agree?
RE: "PROOFS WERE STRUCK TWICE on specially prepared planchets."
OK. BTW the easter bunny needs your address. He has some letters from the Great Pumpkin that santa signed for your to give to the tooth fairy.
To test your belief, 1) check 19th and early 20th century proof coins. Look for consistent offset doubling; 2) investigate work hardening of silver-copper alloys; 3) examine re-annealing of silver-copper alloy including thermal distortion; 4) locate a Mint documents from the 19th (after 1855) and early 20th centuries stating that proofs were struck twice - preferably by Keebler cookie elves when on vacation.
The letter below might help with some other misconceptions. (If proofs got 2 blows, don't you think Superintendent Dressel would have mentioned it - he mentions a lot of other things?)
Lastly, please read the book. A lot of work went into making it as complete and accurate as possible. If you disagree with some of the content, use the footnotes and bibliography to locate and review the sources for yourself.
The proof 1962 Franklin half dollar shown in this thread is incontrovertible evidence that (at least some of) the proof coins of this era were struck twice. If any proof coins of this era were only struck once, then those would be the exception, not the rule.
I have done a lot of over-striking and have studied the results. The artifacts seen on this coin are entirely consistent with a second strike that was not perfectly aligned with the first strike. I see exactly two strikes (no more, no less), and no "machine doubling" on this coin.
What some here may not have considered is that the second strike, if not perfectly aligned with the first strike, will cause the first design elements to be significantly flattened and distorted.
I find this all very interesting.....And probably should just keep reading quietly.
But I wanted to throw out the possibility that the "ghosting" wasn't apart of the striking of the coin at all, but part of the die making process? Say, a "first squeeze" in pressing the die blank into the hub made a partial impression of the lettering, which was mostly eliminated in the final product. But small outlines remained in the fields of the finished die?
One could argue that the die polishing required for a mirrored proof of the era should have eliminated most of any remaining elements....but who knows.
Just looking at it from a different angle....
Re the 3-4-43 letter, I find it curious that the Mint would say that the wartime nickel composition would not make satisfactory Proofs. I have seen many nice 1942-P Type Two Proof nickels.
Now, I can see the 1943 zinc coated steel cents making lousy Proofs.
I always thought this was called 'flat field doubling'. The first strike produced machine doubling, and the second smashed it flat into the field...
Yes. I think likely just some personal bias there.
@RogerB said: "Lastly, please read the book. A lot of work went into making it as complete and accurate as possible. If you disagree with some of the content, use the footnotes and bibliography to locate and review the sources for yourself."
I have not finished "From Mine to Mint" from beginning to end yet. I have not read your latest book about Proofs at all. I have only read about the 1907 mintage in your "Renaissance" set. MY WORK IS NEVER DONE.
Either is yours - keep writing and posting.
MR. Bill
has revealed my Identify in another thread so I'm out of the closet. 
dcarr - Thank you for your response and the experiential insight. I have a few other strike-doubled (NOT MD) proofs that I have squirreled away.
I think your insight on Strike Doubling is also validated by a previous post by CaptHenway through an observation he made of details on the letter "Y".
I highlighted the flaws he observed in the image below. They are indeed identical and are not artifacts of lens or lighting. This evidence would support multiple strike doubling. The "shelving" friction or scrape would normally wipe out any trace of these flaws on the MD spread. This new revelation puts the "multiple strike" origin for the ghost image in doubt.
With sincere gratitude for this new attribution being addressed: Sans Machine Doubling or Strike Doubling, back to the original topic. Where did the ghost image come from??? Opinions Please.
Actually, I was talking about the right arm of the "y." Look right above the fork in the Y. This dot repeats on the shelf. Now look about one-third of the way up the right arm at two parallel lines that repeat. Still further up the arm are two single lines that repeat.
The pink outline in the image below shows the perimeter of the Y from the first strike. The blue outline shows the perimeter of the Y that was formed from the second strike.
First, @CaptHenway’s Comment:
Yes, I see it. What threw me off was “This is on the other side of the letter from the ghosting, …..” However, the yellow highlighted areas, left and right strongly support @dcarr’s conclusion that this coin is an example of Strike Doubling.
I personally consider true “Strike Doubling” to be an error and collect this anomaly.
True multiple “Strike Doubling”, as exhibited on the pictured coin, can only occur on coins that are intended to be struck multiple times during the normal minting process. Proofs would be the most common example. In this case, “Strike Doubling” is not an artifact; it is consistent with an error in the intended result. This hypothesis is supported by the overlapping markers caused by the shifting/rotation between the two strikes of the coin and is not a result of the ejection process. This anomaly is a direct consequence of the inherent multiple strike minting process. If the SD is caused by any rotation or pivot of the die, collar, or coin between strikes, the anomaly occurs during the production of a coin and thus is an unintended effect through a failure of the minting process integrity. This would be the quintessential definition of a “Mint Error”.
Next @dcarr’s Post:
Wow, I think you nailed it. You have explained the ghost image for a Strike Doubled Proof Coin! The two are interdependent and not separate issues. Your image unequivocally shows how the ghost image is an artifact of Strike Doubling. If I interpret your image correctly, the first strike of the coin raises the devices on the coin. Then, something causes the coin, collar, or the die to shift along the horizontal plane. For the coin pictured, if the shift is in the coin then the direction was counter-clockwise. Conversely, if the shift is in the die then the die rotated in a clockwise direction. During the second strike, the raised portion of the devices are “smashed” but even at the high pressure of the proof press, the raised metal of the devices from the first strike prevent the second image from being fully pressed. Thus, at least for the pictured coin, the incused area of the die outside of the device overlap only “kissed” the surface of the coin. Hence the Ghost Image”. Kudos, dcarr, that is a nice piece of deductive reasoning. (Nice work on the markup too.)
Below is the aggregate markup that illustrates all the elements to establish the origin of the Ghost Image.
As stated above, I think Strike Doubling is a true Mint error. If one considers the technicalities of SD, it suggests that SD is much rarer than Hub Doubling. Dies that generate Proof Double Die coins (DDO/DDR) are usually in service for the life of the die. The error that created Proof Strike Doubling may only last for a single coin or a few hundred before the press operator is alerted to the anomaly. In the image below, look at the beveled wedge and the extended crease. Something “violent” occurred during the first strike of this coin. This may have contributed to the offset rotation of the second strike. The Proof press operator is habitually tuned to the rhythm of the coin press. Makes sense that this violent occurrence would have come to the operator’s attention. In addition, a contributing rarity factor is that true Strike Doubling can only occur on coins that, by design, receive multiple strikes and are therefore are limited to a minor portion of the Mints total production for that year. Any Mint regular production coin can have DDO/DDR Hub Doubling.
Any further comment, clarification, or opinion would be appreciated.
Just to be clear...then Proofs were struck twice?
Tom's good eyes + the OP's overlay nailed it.
Just as was done here, back in the day, authenticators could confirm a coin was a genuine double struck error by matching tiny diagnostics present on a die that transferred to both strikes.
As to strike doubling being something special on a Proof or single strike coin, I say no, no, no, and never. LOL. However, "Ghosting" on Proofs due to two offset strikes is special.
You've got the annotation backwards. The pink outline is the perimeter of the "Y" after the first strike. The blue outline is the perimeter of the "Y" as imparted by the die on the second strike.
I see a mostly lateral (linear) shift between the strikes, not a rotational shift so much. A significant rotational shift between two full-force strikes would be highly improbable. But a lateral shift is very possible.
So how could a lateral shift occur between two successive full-force strikes ? There are two possibilities:
.
1)
The upper die was a little loose in the coin press.
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2)
When fully struck, a planchet will typically expand radially up against the collar. At this point the coin will be tightly lodged in the collar and then the coin press will use the lower die to push the struck coin out of the collar. On proof coins such as the 1962 Franklin, there are two successive strikes in the collar before the ejection.
For the planchet to be able to fit into the collar, there must be some clearance (the planchet diameter is smaller than the inside collar diameter). If the planchet was a little smaller than normal, it may fall into the collar in such a way that it is touching the collar at one point, but 180 degress from that point there is a wider-than-normal gap between the edge of the planchet and the collar.
Then the die comes down for the first strike. The planchet metal moves radially but also has an overall tendency to move towards the larger gap. This movement can cause the upper die to deflect laterally by a small amount. When the upper die is retracted, it is free to move back to the original position centered above the collar. When the die comes down again for the second strike it is not in perfect alignment with the image from the first strike.
.
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I have had the entire upper die holder in my coin press come loose while striking. Even so, that did not result in any doubling of the struck image, even with three or four strikes. So I believe scenario #2 is what occurred on the 1962 Franklin in question.
Please post pictures of the entire front and back of the coin if you can.
@dcarr: Sorry for the delay but could not get in last night, I think the Board was down.
Below are the full Obverse & Reverse images of the 1962 Proof. These shots are full 5.5MB unedited JEPGs so if you download them, you can manipulate them with any Photo Editor. I use Paint.Net.
I understand your explanation on rotation vs lateral and I agree. One point: It is my understanding that the term “second die strike” is technically a misnomer. My reading suggests that in the production of a proof coin, the die never actually physical leaves the surface of the planchet. The term “second strike” refers to the reapplication of hydraulic pressure from the hammer and anvil press. However, your suggestion of lateral movement still fits this scenario since metal, under pressure, will always flow toward the path of least resistance, hence the “relief” image of a coin. I guess this is a discussion for another post.
As to my backwards annotation, I acknowledge the error. I know how I made the mistake despite your clear statement “The pink outline in the image below shows the perimeter of the Y from the first strike. The blue outline shows the perimeter of the Y that was formed from the second strike.” I made the mistake because my mind could not see the scenario where the (partial?) First strike creates the ghost and the Second strike creates full devices.
With sincere respect for your expertise and experience, I am having a problem with the First Strike and Second Strike sequence. In a full force first strike, how does only the ghost image remain after the second strike? Does the second strike partially obliterate the first strike devices and reduce them to a shadowy field? In your markup of the “Y”, the Blue outline Second strike appears to show a “Y” that is underneath the Pink outlined First Strike “Y”. How can this be if the Blue outline is the Second strike? Another issue with the sequence is the @CaptHenway’s duplicated markers. If the First Strike were the ghost then, on the Second strike, would not most of the field markers on the entire coin be duplicated? However, on the “Y” image, the duplication only occurs to the field markers that are within the shelf of the spread. This limited overlay suggests the ghost is the second strike. One final issue is the “2” image. After doing several Paint.Net overlays, I cannot reconcile the Ghost first strike sequence with the “2” image. On the bar of the “2”, the crease to the left of the gouge lines up perfectly with the “2” ghost. I think this would mean the ghost was the second strike.
Please understand, I am not being argumentative or disrespectful. Asking an expert, such as you, questions is the best way to understand where my reasoning goes south. If questions expose my ignorance, it is the price I am willing to pay to learn.
I thank you for taking the time and expending the effort to “school” me.
Geez Roger. everyone knows they were done by magic space pixies from the third moon of Pluto!!!
All Proofs and Master Coins, regardless of time period, were struck once. There are a small number of early MCs struck twice on a screw press. The piece didn't quite strike up so they gave it another whap, or even just a mistake.
JD and I have discussed modern proofs on several occasions. For modern proofs, the hydraulic press had a heavy weight above the upper ram. When the dies were fully closed, this weight dropped rather forcefully providing a second pressure pulse to improve the strike. I really wouldn't call it a "double-strike" as the dies never opened. IIRC, JD saw this process at the Philly mint, I'll ask him. I saw it some time ago on the History Channel or one of those, I think on "How It's Made." That is a possible cause.
Also, the dies at this time were frosted using acid. There are two ways of doing that. The first is simply to immerse the whole face in acid, then in hot wax, scrape off the excess wax leaving wax only in the recesses to protect the frost, polish the die, and then remove the wax in the recesses with solvent.
The other, which again I saw in an old documentary, was to cover the face with a film resist and then painstakingly cut away the film around the devices, then acid dip.
Either method could leave ghosting around the devices. Note the rather blobbish looking areas on the Y and W. Looks likes "acid spill-over."
Metal flows in to fill the space and I would think that the space shape could be part of it. Second the heat as it runs many pieces is changing. Looks like drag to me. Then again I might be way off on that.
Best place to buy !
Bronze Associate member
I have never heard of this type of press with a two-step process that first squeezes the coin and then drops a heavy weight onto the hammer die. Can you please provide the documentation of this device, and/or a picture or drawing?
Thx
TD
Hi Tom,
As I said, I saw it in a TV documentary. I'm pretty sure it was on the History Channel, "How It's Made" I think. I didn't bother documenting since I have no interest in modern processes. You can try contacting them. If I recall, JD saw it in person, so you can drop him a line.
Also, could be in Cooper. I'll take a look.
@Rittenhouse said: "Either method could leave ghosting around the devices. Note the rather blobbish looking areas on the Y and W. Looks likes "acid spill-over."
Enjoyed your insight on this topic. However, the sentence I copied above 100% misinformation about the cause of "ghosting." It also has nothing to do with "frosted" dies. Oops, I should have posted...IMHO.
PS I've been thinking about this for a few days while looking for some examples to post and I realized that in forty years I have never seen this characteristic on any coins except for "modern" (after 1936) Proofs!
The Only time I've seen something similar on a coin has been an overstrike (earlier design struck out) or a double struck error coin with a microscopic amount of rotation between strikes.
Despite the claims that proofs of this era were struck on a hydraulic press, I believe that all post-war (and possibly many earlier) proofs were struck on a regular (mechanical) coin press. Hydraulic presses are slow. So why would the mint use a slow press to stamp 16 MILLION proof coins in 1962 alone when a faster coining press would do the same job ? If only one press were used to strike 16 million coins in one year, running 24 hours a day for 365 days, it would have to produce one coin about every two seconds. This doesn't count any likely press down time, shift changes, etc.
There are two main reasons for having multiple strikes on a proof coin:
1) The relief is more completely formed.
2) The first strike causes radial movement of the planchet metal. This will result in a significant "cartwheel" luster effect, even if the die was polished. So the first strike forms the majority of the coin relief. The second strike imparts the die surface texture (polish) to the coin. For this to work, the die must be retracted completely off the surface of the coin between strikes.
Of these, #1 is a relatively minor effect and #2 is the main reason for striking proofs twice.
The fields of a coin correspond to the highest (in relief) areas of the die. In other words, the fields on the die are where the die penetrates the deepest into the planchet. The fields of the die are also where the highest stresses are. These are the areas where planchet defects and irregularities are least likely to show after the strike. So the relief from the first strike tends to be mashed out more where the fields of the second die strike land. The thin ghost outlines are where the fields of the second die strike mashed out the relief from the first die strike. The notches in the lettering are the result of both strikes overlapping on raised devices. These ghost outlines would likely be totally invisible if not for the polished proof finish, which makes them much easier to see.
Hmm, so you then must believe that the 1943 letter from the Superintendent of the Mint quoted above by Roger and stating that proofs are struck on a hydraulic press is fake or some sort of official cover up? How about the statement on page 126 of the "1902 Mint Report" which notes that, "A quick-acting hydraulic press, of 350 tons capacity, designed to strike small medals and proof coins when quantities are required, has been procured"?
And how about the Mint-produced videos on YouTube which have also been shown on the History Channel showing proofs being struck with a hydraulic press? Should we take it that this is some sort of multi-decade, multi-media gov't conspiracy to hide the real truth? Are the black helicopters gonna come looking for me, JD, and Roger?
And why do you believe that hydraulic presses are slow? Shoot, even back in the 80's when I was a process engineer we had fast-acting hydraulic stamping presses that cycled 40/min, And that was just a small manufacturer that certainly did not have the resources of the federal gov't.
Why would you believe that a high volume manufacturer like the Mint would only have one proof press?
What I wrote was "post war proofs". FYI that means 1950 to at least 1964, which is the time period of the 1962 Franklin half dollar in question.
What was being stamped in the "Mint-produced videos on YouTube" ? Perhaps you could post the link.
I have a modern 40-ton hydraulic press. For a hydraulic press it is pretty fast. But the stamping speed is considerably slower than my Mechanical Gaebener.
The higher the tonnage, the slower the hydraulic press, in general. But some hydraulic presses can deliver more tonnage than mechanical presses. That is why larger medals and other things (like the US Mint 5-oz silver ATB coins) that require more than about 400 tons are often struck on hydraulic presses. A coinage press capable of striking circulation Franklin half dollars can certainly strike proofs as well (and do it much faster). My Graebener coin press was utilized at the Denver Mint to strike all the commemorative silver dollars that were produced there from 1986 to about 2001. The Denver Mint did not use a hydraulic press for any of the collectors coins (commemoratives and mint sets) or for any of the 1-1/4 inch presidential medals that were made in Denver during that time.
I didn't write that I believed that. I stated that IF only one press was used it would have to produce one proof coin every two seconds, 24 hours a day for 365 days. Suppose they had five presses dedicated to making only proof coins. Then each press, on average, would only have to produce one coin every 10 seconds. This is certainly within the realm of possibility for hydraulic presses. But consider the manpower that would be required to run these relatively slow presses. In 1962 there was a coin shortage underway and the US Mint was doing everything possible to produce as many coins as possible. It would not make much sense for the US Mint to divert such significant resource to proof coin production when it could be done faster and more efficiently using mechanical presses.
For a dropped weight to have any effect, it would have to be a very heavy weight dropped from a significant height. Hydraulic presses are not generally as good at lifting (moving upwards) as they are at stamping (moving downwards).
Also, this type of jarring could damage the hydraulic cylinder. So I doubt your contention that a hydraulic press with a dropping weight attachment is a reality. But if you have any documentation, I would certainly like to see it.
There is, however, a type of Graebener mechanical press which can produce multiple strikes without lifting the die. After the first strike, the strike mechanism retracts upwards but it leaves the die block resting on the coin. Then for subsequent strikes on the same coin the press "slaps" the back of the die block. Here is a video (the muti-strike part is shown starting at 1:00): https://youtube.com/watch?v=85mmOwycLxY
Note that with this press, even though the upper die is not lifted between strikes, everything is allowed to "relax" between strikes. So double-striking artifacts could still occur with this type of arrangement.
Question for @dcarr:
First: I corrected the image in my previous post (originally 02/014/2018) to properly reflect your order of strike on the two images. Again, my apologies. Obviously, I cannot correct the “Quote” image in your post underneath mine.
Second: On further examination of the coin, I was wrong. The First “strike” is the Ghost Image. Thank you for the expertise to help me see this.
Third: I am doing further research to try to determine what was the anomalous event that caused the ghost image “shift”? During my research, I spent hours trolling the Internet and the Library of Congress for any documents, report, or illustrations that dealt with the minting of Proof coins from 1950-1963. More on this later. Also, I have found additional details on the coin that may help and will post the new images.
One question for you, out of curiosity, are the dies on your press aligned horizontally or vertically?
My Graebener press is vertical-acting. Horizontal-acting mechanical presses are extremely fast because they can use gravity to assist in feeding and extracting struck coins. But vertical-acting coin presses are typically used for collector coins that are manually fed.