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 Replies: 41 / Views: 13,600 |
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Bedrock of the Community
United States
17884 Posts |
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Rotated Dies are errors and not varieties. I think someone mentioned that earlier. Think about the minting process. An error is a singular event that does not include a defect in the die (pairs). A variety is created when something is wrong with the die/dies. It's not quite so black and white. Some rotated dies are that way because the flat ground on the body of the die is ground in the wrong place (The flat is a flat side ground onto the body of the die to either act as a key for inserting the die body into the press or to provide and area for the set screw to press against to KEEP the die from rotating.) If the flat is ground in the wrong place then EVERY coin struck from the die pairing will show the same rotated die alignment. This would make it a variety and not an error. Most modern rotated die coins are the result of misplaced die flats. Back when the mint was using a dual die arrangement the dies were placed so the distance from the center of one die bodie to the center of the other was LESS than twice the radius of the die body. SO the only way to put the dies into the press was to put the flats of each die together. This had two advantages. It would lock the dies together so they COULDN'T rotate. And it automatically put the dies into the press in a set position so you didn't have to worry about them not matching the dies from the other side. But to do that the flat has to be ground in the same place on each die body. |
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Valued Member
 United States
314 Posts |
MOrgan, if you want to expand your rotated dies, start checking out the Large Cents and U.S. Two Cent coins. Rotated dies do not appear uncommon among some of the earlier large cents (19th Century), and I've got a couple of Two Cent coins that have (what I believe) is significant rotation. I agree wholeheartedly about your assessment as to whether or not it is the obverse or reverse that is rotated. Fantastic comment. Don't forget to look among the Half Cents either. They tend to have regular die rotation of significance.  Edited by Dcreek1968
09/07/2010 8:35 pm
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Moderator
 United States
16679 Posts |
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I collect all coins with rotated dies; especially Morgans Here's one of mine:   1897 IHC almost 180:   swcoin.ecrater.com
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Pillar of the Community
3660 Posts |
Quote:1878-CC MS-63, VAM 22 with Rotates Dies. The rotation is a little more than 90%. This is a unique coin, in my opinion; only one has been reported to date. Nope, not unique by a long shot, and there have been more than you can count on all of your fingers and toes reported to date. In fact, 1878CC vam-22 with 90 degree rotation is probably one of the most (if not 'the' most) common Morgan with rotation. Quote:
On the rotation, some people use the bottom of the coin to determine CW or CCW... some people use the top of the coin. Logic says use the top. My coin would be 270 degrees CW or 90 degrees CCW. The reason why the certification says Rotated Dies is because who can determine whether it is the obverse or reverse that is rotated? While I do agree with your final assumption of the upper die being rotated, my source of logic is different. On a Morgan dollar, the lower die sat snugly in a cup (die stake) and was held from rotation by a set screw. This cup rested on the main arch in retracted (or strike, or anvil) position. The upper die also sat in a cup, held from rotation by a set screw, but was suspended by linkage that moved and flexed with each strike. The impact vibration was greater on the upper (obverse) die than on the lower (reverse) die. Now consider this: The planchet acted as a buffer, or pillow, between the downward impact of the upper die to the lower die. Which die would sustain the greatest impact of strike? Which die would therefor be more apt to loosen from its setscrew? Quote:
Think about the minting process. An error is a singular event that does not include a defect in the die (pairs). A variety is created when something is wrong with the die/dies. I really don't think that I can agree with 'any' of that. If the definition of an error is a singular event, then errors are relegated to only Strike Doubling, misaligned dies and maybe some other press originated issue. A variety is a Cud or a die break, or strike through, or rotation? What then is a specific die pairing considered? (For instance, CBH O-103 versus O-114, or Morgan VAM-22 versus VAM-7)? Your 1878 VAM-22 with 90 degree rotation is a variety, but what is the the aspect of this particular coin that makes it a variety? |
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Moderator
United States
16679 Posts |
An error is not human manipulated in the sense of not being controlled. A variety, had human manipulation at some point.
swcoin.ecrater.com
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Pillar of the Community
3660 Posts |
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An error is not human manipulated in the sense of not being controlled. A variety, had human manipulation at some point. (I think)......  ......Well said anyway. |
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Bedrock of the Community
United States
17884 Posts |
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The impact vibration was greater on the upper (obverse) die than on the lower (reverse) die Can you be sure obv was the upper die and the reverse was the lower one? |
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Pillar of the Community
3660 Posts |
Yes, I am as sure as a person can be without actually coining the pieces myself. Although many vammers, CBH collectors, and other variety 'experts' consider that they are involved in coin forensics, they seemingly use the word 'forensics' far too loosely. Die identification is just that, identification of one die from another, and that is the end of it. Forensics, on the other hand would tell the 'how' something happened and in which configuration or situation. Not only is documentation found in the Mint Archives mentioning die configuration, it is also obviously evident on partial collar coins, (the effects are side specific), regardless of year or mint. Just try to find a railroad rim on the reverse side of any Morgan.....just try. While you're at it, try finding a Peace dollar with collar clash marks on the obverse. While credible documentation of the Peace dollar dies being reversed from the Morgan set up has not yet surfaced, evidence on the coins themselves is also side specific. |
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Bedrock of the Community
United States
17884 Posts |
Forensics isn't a ba word bcause examination of the coin can tell you which was the upper and which was the lower die. it can be determined by the pattern of fine scratches an scraped metal withing the reeds of the edge that are created when the coin is pushed up out of the collar. (It is harder to tell but the same technique works for plain edge coins as well.And at time these features can tell you that the dies were NOT installed in the way they were normally thought. On some series there are records that state how the dies were oriented but examination of the coins will show that in some years the orientation was reversed. Unfortunately as the coin wears the clues become harder to see and may disappear completely. So the techniques works best on higher grade coins and it works better on larger coins. It is quite easy to see on ASE's which is also a series that sometimes shows reversal of orientation for one year to another. Quote:
An error is not human manipulated in the sense of not being controlled. A variety, had human manipulation at some point. But a rotated die could still be the result of either one so it could still be either and error or a variety. Edited by Conder101
09/09/2010 09:05 am
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Pillar of the Community
3660 Posts |
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examination of the coin can tell you which was the upper and which was the lower die. it can be determined by the pattern of fine scratches an scraped metal withing the reeds of the edge that are created when the coin is pushed up out of the collar. Trust me Conder, I am not trying to put you on the spot here, but this concept or technique interests me. This is something that I would like to know more about, as I am ignorant of it. If I am understanding this correctly, the fine lines in the reeding that you mention, would be running vertically, and be heavier near the lower die than the upper? I have never paid much attention to these lines at all before. These are (those) inherent in the collar from when it was swagged? If so, sometimes they may be raised and sometimes incuse between the reeds depending on whether or not an attempt to clean up the collar was made after swagging. Are these the lines that you refer to? I don't have the means to look that closely, but I will try to pay better attention in the future. (Very neat stuff)! Edited to add: I have my own definition of error, and that is 'anything that is not intended' and therefor, I consider rotation to be an error..... (only). Edited by zeewool
09/09/2010 09:41 am
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Pillar of the Community
3660 Posts |
Conder, It just dawned on me that a foolproof way of determining upper and lower dies would be (if there were a device or measuring tool to accomplish it), to square the coin at one side to its edge. The collar (being cut by a swag) is slightly cone shaped, smaller at the bottom near the lower die than at the top near the upper die, so this effect would naturally transfer to the coin itself.
edited for spelling.
Edited by zeewool
09/09/2010 09:56 am
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Pillar of the Community
3660 Posts |
Conder, I am still contemplating the "pattern of fine scratches an scraped metal withing the reeds of the edge that are created when the coin is pushed up out of the collar".
Why would this be an indicator of die configuration? Since ejection releases the coin from the collar, it may be considered that these scratches and scrapes are caused more likely by strike than ejection 'eh? I could see it going either way, but I still don't comprehend the rationale of scratches between the reeds on a coin as indicative of anything at all. If these scratches are between the reeds on the coin, this would mean that the collar is flawed on the teeth themselves. Possibly broken teeth tips? More likely an effect of swagging though whether or not the effect is uniform around the coin.
As far as checking the coin edge for bevel due to the conical shape of the collar, I would think that if three UNC coins were stacked with obverses facing left, and this stack placed between the jaws of a digital caliper, the bevel may be seen. I would forget the readout on the caliper, but hold the set up to the light, and notice the light showing through between the stacked coin edges. I haven't tried this, as I have no coins or calipers, but I would think that it should would work.
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Valued Member
United States
297 Posts |
i used to search all my coins for this but after I while I just gave up .
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Bedrock of the Community
United States
17884 Posts |
You have the correct understanding about the scratches in the edge of the coin. The collars are not perfectly smooth. On a microscopic level the collar has imperfections and raised defects. When the coin is struck the metal of the coin is forced around these microscopic defects. Then when the coin is pushed up out of the collar a scratch is created on the edge of the coin from the level of that defect down in the direction of the lower die. The closer the defect is the upper die side of the collar the longer the scratch is there will also be fewer scratches on the upper die side of the coin and more on the lower die side. Something else you can look for are little "rolls" of metal around the edge of the reed valleys where the edge meets the rim. This metal is the metal scraped from the edge of the coin by the defects in the collar. All of these features are more naturally pronounced when the collars are new and will become less prevalent as the collar ages or as the coin wears. Quote:
It just dawned on me that a foolproof way of determining upper and lower dies would be (if there were a device or measuring tool to accomplish it), to square the coin at one side to its edge. The collar (being cut by a swag) is slightly cone shaped, smaller at the bottom near the lower die than at the top near the upper die, so this effect would naturally transfer to the coin itself. That would work too, but the taper of the collar is probably not more than about a thousandth of an inch over the thickness of the collar which is several times the thickness of the coin. It may be vary difficult to square your measuring device the coin and the taper of the coin over the thickness of the coin would be very small and probably hard to measure. Not saying it can't be done, but I don't have that kind of equipment. Quote:
As far as checking the coin edge for bevel due to the conical shape of the collar, I would think that if three UNC coins were stacked with obverses facing left, and this stack placed between the jaws of a digital caliper, the bevel may be seen. I would forget the readout on the caliper, but hold the set up to the light, and notice the light showing through between the stacked coin edges. Good thought, that might work. Quote:
Since ejection releases the coin from the collar, it may be considered that these scratches and scrapes are caused more likely by strike than ejection 'eh? Ejection does not "release" the coin from the collar, it FORCES the coin up and out of the collar. The forsce of the strike compresses the planchet tightly against the collar. You probably could not force the coin out of the collar just by hand. So the coin metal is wrapped around any tiny irregularity in the walls of the collar. Whn the coin is forced out those irregularities don't move. Something has to give and that something is the softer metal of the coin. |
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Pillar of the Community
3660 Posts |
Yes, we are in agreement and on the same wavelength on everything.....(with the exception of this): Quote:
Ejection does not "release" the coin from the collar, it FORCES the coin up and out of the collar. While this may be just a matter of semantics, I contend that 'release' is the correct term. The only force necessary to eject the coin is that exerted to break the the coin away from the collar at strike position. After the initial break, a pinky finger could push the coin up the rest of the way out of the collar. That is the reason that the collar is shaped the way that it is. This too would be hard to measure though, as the travel of the coin out of the collar is only about 1/8". In any event, we do agree that there 'are' physical means of determination of die configuration (far beyond the popular techniques of speculation or relying on the speculation of another). Good talk, I like folks who can think for themselves. Bravo. |
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Replies: 41 / Views: 13,600 |
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Posted 09/07/2010 8:32 pm
