I posted this within an unrelated thread and I think it would be better to dedicate a new thread for this topic because I'm still confused. After reading about mechanical doubling on Wexler's site (link below) and here on CT, I'm confused as to why there isn't more doubling throughout the coin on almost every single design element most of the time. This question is different from how to identify MD (e.g. flatness of doubling, no rounding and very low relief, etc.). After reading about MD, the parts connected to the die(s) are loose, which causes the MD to occur. The planchet itself is secured by a collar, so the die is what's doing the moving, causing the doubling. So, if the entire die is what's rotating (pivoting from the center and not the edge) and/or shifting in one direction, then at almost every conceivable possibility, shouldn't MD be evident on every single design element (e.g. the portrait, words, date, MM, monogram, etc.)? Why is it that many if not most of the MD that's seen (at least by me) only on just the date, or a combo of the date, MM, and letters. - it seems to be restricted to just those features of the design (although Wexler does provide an example of MD on Kennedy's portrait). Unless the die pivots at the edge, then it would hit and damage the collar and the rim of the coin would be flattened (always I presume) and cause doubling on a small section of the coin (but every coin with MD in a small section like just the date has an uninterrupted, full rim)... or unless the planchet itself gets struck twice, and pivots from one edge of the planchet off the collar, then MD limited to just the date, MM, letters, etc. makes sense. Is one of these possibilities described in this paragraph the answer? I feel like there's something I'm missing here. Thanks in advance for any clarification! http://doubleddie.com/144822.html
There is a lot more to it than one might expect because to protect the actual press, a certain amount of "movement" is built into the process. Die's may not be perfectly aligned at a 90 degree angle. The mechanical ejection process (which is a source of MD) may be just a smidge out of sync with the press. An infinitesimal fraction of an inch can cause really dramatic "mechanical" doubling when looking at an item under "magnification". eMail Mike Diamond. Maybe he has a paper written somewhere in his files that can give you a description from the physics side of the house.
Die movement tolerance for shock absorption purposes makes sense. But I would think, at least conceptually, that the ejection process would still be a shift of the entire planchet and thus every design on the coin should shift uniformly and not just, say, the MM (I know I'm still missing something here). I'm sure you have all seen this video, and at 8:10 in this video, the ejection takes place as a push (at least in 1940, but they still had MD back then). It's an entire lateral shift of the planchet.
Heres a good article for you: Is My 1969-S Cent The "Real" Doubled Die?by Ken Potter - NLGCopyright Ken Potter 2002 Revised w/new images and additional text 2013 Image No 1. Genuine 1969-S Doubled Die Cent. Coin courtesy of Mike Tremonti of MI. Image No 2. Genuine 1969-S Doubled Die Cent. Coin courtesy of Mike Tremonti of MI. Image No 3. Genuine 1969-S Doubled Die Cent. Coin courtesy of Mike Tremonti of MI. Image No 4. Genuine 1969-S Doubled Die Cent. Coin courtesy of Mike Tremonti of MI. Without question, the most frequent question I field in reference to Doubled Dies revolves around the 1969-S Lincoln Cent. There are two key reasons for this; the first is that the 1969-S Doubled Die is an extremely valuable coin with the one pictured at the top of the page (Images No. 1-4) exceeding $125,000 in a Heritage Auction in 2008. As a consequence, folks are naturally interested in knowing more about a coin that is of a vintage recent enough to potentially still be found in pocket change and a date still being offered in brilliant uncirculated roll quantities at modest prices. The second reason I get so many questions about this coin is the fact that this date, along with the 1968-S and 1970-S cents, arguably share the distinction of boasting the largest percentage of examples of Strike Doubled coins within their respective mintages over that of any other US coins. The fact is, it is hard to find a roll of cents for any of these dates without finding pieces exhibiting this affliction. Although worthless (and technically a form of damage) Strike Doublingis often confused by non-variety specialists as being Hub Doubling or what we commonly refer to as a Doubled Die. Strike Doubling is often referred to by others as "mechanical doubling," "machine doubling damage," "shelf doubling," "die bounce," and a host of other terms. The trick to learning if your coin is the valuable Doubled Die is to simply match your coin to the photos shown above in Images No. 1-4. If you have the valuable Doubled Die, it will exhibit the doubling in all the areas exactly as shown in the top four images with the only exception being if it also has Strike Doubling (read on). Another diagnostic of a genuine 1969-S Doubled Die is the sort of pebbly or crumbing look of the fields around the date. This pebbly look is most apparent between the 9 and 6 and to the right of the final 9 of date. If your coin is Strike Doubled, (as are 99.9%+ of the finds), it will show doubling in varying locations, directions and strengths on the coin (which can vary greatly from coin to coin). These areas of doubling may be in similar locations to the genuine Doubled Die but will not show the well-rounded, overlapping, raised secondary images you see on the Doubled Die. Image No 5. Strike Doubled 1969-S Cent. Coin courtesy of Ali Siemsinginofski of MI. Conversely, Strike Doubling, which is the result of die-bounce due to vibrations in the press, occurs within the split second after the coin is struck and will typically show as flat shelf-like extensions of the doubled characters. There will be no open field areas in-between the doubled images as are clearly seen on the genuine article. On many extreme examples of Strike Doubling you will actually see a narrowing of the original raised character from whence the lower shelf of doubling originated when that portion of that character was smashed down into the field. This narrowing of the original height of a character is not always obvious but is another diagnostic of Strike Doubling to look for. I show Strike Doubling on the 1969-S cent in Image No. 5. I repeat that Strike Doubling may show in any direction in any areas of the coin either widely across the entire design or just restricted to just one of two elements. It may be more closely doubled or more widely doubled than shown here. It is also not limited to this date but shows up on just about every date, denomination and type of coin ever struck by any Mint. But wait, that's not all! Of the first four genuine 1969-S Doubled Dies that I actually held in my hand, every single one of them exhibited a tiny bit of Strike Doubling on the "S" Mintmark. While it was hardly noticeable, it was nonetheless there. In the meantime, for decades experts have been telling folks that if the 1969-S they have with doubling, also shows doubling on the "S" Mintmark that it was in fact not the genuine Doubled Die. For decades I have had to correct the misinformation of these well-intended folks were giving out because there was really no reason why a genuine 1969-S Doubled Die could not also be afflicted with strong Strike Doubling. I told folks that the doubling of the S was a pretty reasonable clue that it was not the genuine Doubled Die but that it was not a 100% positive indicator. In late 2007 my position was finally vindicated when I saw another 1969-S Doubled Die that also boasted strong Strike Doubling on the date and other areas including the S Mintmark. The image of the date area of that coin is shown below in Image No. 6. So now you have the rest of the story. Image No 6. This is a genuine 1969-S Doubled Die that also exhibits very strong Strike Doubling on the "96" of date and the Mintmark. ## For more detailed information on Doubled Dies and other forms of doubling, we recommend that you visit our Educational Image Gallery Educational Image Gallery
Then you would be over simplifying the entire process which occurs hundreds of times a minute. A literal blur of activity. Planchets can sometimes "stick" to the anvil portion of the die set and even the very slightest of sticking can cause the planchet to tile during the ejection process. Remember, the finished coin is literally being pushed out of the die. This is really a physiologically intense process which can produce some minor and also some major mechanical doubling. BTW, its not that you are "missing something" as much as it's that you not "seeing" all the varying factors that contribute to mechanical double in order to protect these extremely expensive presses.
ok just read Ken Potter's explanation. It's vibrations (like the movements for shock absorption?) that cause doubling. So vibrations cause doubling on the letters and numbers only and not the larger (width and relief) portrait because... the portrait tends to be secured in place by the die while the design elements surrounding the portrait are not as secure, causing the MD from the vibration in the split second the planchet is pressed (first design created, highly secure while in pressed position) and being ejected (relatively loose and shifting/"smearing" occurs) (?). If that's the case, then I can see how some design elements don't necessarily have MD, while only just say, the MM has MD. However, I would still think that in such a limited area that MD would be more rare, than say, die deterioration because vibration affects other areas of the planchet equally. Obviously, though, that is not the case.
This link explains isolated machine doubling a little also. http://www.error-ref.com/isolated-machine-doubling/
When considering MDD (Machine Damage Doubling) a couple key words to consider are bounce and die deterioration. Larry Nienaber
That makes sense! I got it the other way around, it's the higher relief and not the lower relief features that catch the die upon ejection while there is vibration.
In this 2014 Silver Eagle example, however, the relief is equal in height on the A to all the other letters. Yet, doubling is only observed on the inside of the A. If it's die deterioration, the rest of the die's impression onto the coin looks immaculate and sharp. Assuming that this is MD, can isolated MD account for this, or would it be a form of say, a die crack or die "chip"? Unless this is a form of isolated DDD.
[/QUOTE][/QUOTE] Great informative video - but with that background music I was expecting the Little Rascals to make a cameo apperance somewhere in the mint!
Also, the OP should "understand" that its not so much of what you "see" as much as it is what you "understand" about the minting process.
Yes - very outstanding answer. IMO the more power you view your coin under (30-50+X) the more your brain want's to see a major one of a kind error!! Although I would give my left (or right) "canutski" for a 69-S DDO
I'd like to think I would but in all honesty, I don't really think I would. Otherwise, I'd be ordering $25 boxes of cents to go through. I usually get bored senseless after the first 10 or so rolls but............since I moved to California, I have had the absolute best luck I've ever had with finding rare coins. Some were sold for mid to upper 4 figures. Others, at close to a grand. Maybe I should start ordering cent boxes?
As far as I know, the last one found came from a 9 dollar roll of 1969-S, bought from a coin show in Michigan, some people think that 69-s was from a mint set, but thats not true..
The 11/24/2014 edition of Coin World reported about a collector which found one searching rolls which is what I based my response on. Terry Muth, from Kentucky, says" he discovered the coin after searching through nearly 12,000 Lincoln cents he obtained in 50-coin rolls from his local bank in Louisville. (Home Town of Jennifer Lawrence I might add! ) The coin was graded AU-55 by PCGS and was sold for $19,800 on Nov 2nd at auction.
I can only speak for Michigan, and I know what the article said, wasn't true, I go to a lot of coin shows in Michigan, and thats where I heard the truth from, so as far as articles go, I would have to hear it from the owners mouth, and it looks like she young, and easy to get to say what they want..
Hopefully you didn't copy what the article say, because Terry looks like a girl, not a guy... No pun intended...
