2004-P ddr

[THE PENNY MAN]

Hello all here is a 2004-P ddr which looks like a circle around Lincoln. First one i seen like this, please let me know what this is. Thank you.

[mustbebob]

You have found the mystery cent. I have 4 of them here, and there are actually 2 or 3 different ones. No one has been able to determine what caused the circle, but it is definitely a mint made anomaly. The circle has also been found on some 1998 and 1999 cents.

[JeanK]

That is an interesting anomaly, and I have yet to find one.
I keep thinking that someone at the mint was having a lot of fun with the dies for those years.
Jean

[jcuve]

I examined and photographed one of these a few months ago (I cannot recall the year). A strange anomaly indeed. It would seem something circular made contact with the die - but when or why is a mystery.

[bhp3rd]

I also found one last year and have been holding it to send in. It stays in that roll of "who knows what it is" coins that we seem to get.
This one bothered me also as it is for certain not an added type circle but happened when hubbed?????

[jcuve]

It is just conjecture, but I feel it is an accidental encounter between the die and a centralized part of one of the lathing operations that dies do through as they are trimmed down after the hubbing procedure. I don't think it is a coincidence the circle is in the middle of the design and the most likely reason for something to be in the center of a die is you the need to spin the die or spin something around the die. I have no idea which lathing process it could be as I have not physically seen any of the operations occur before me. I am further imagining the anomaly is getting by inspection as the circular dent is somewhat masked by the design of the reverse and would not expect the anomaly to go unnoticed on the obverse die.

[bhp3rd]

It is just conjecture, but I feel it is an accidental encounter between the die and a centralized part of one of the lathing operations that dies do through as they are trimmed down after the hubbing procedure. I don't think it is a coincidence the circle is in the middle of the design and the most likely reason for something to be in the center of a die is you the need to spin the die or spin something around the die. I have no idea which lathing process it could be as I have not physically seen any of the operations occur before me. I am further imagining the anomaly is getting by inspection as the circular dent is somewhat masked by the design of the reverse and would not expect the anomaly to go unnoticed on the obverse die.

That is a well thought out theory - I had not thought of that but makes some sence. On lathes I've seen and used (not much) they have a positioning point to hold fast the stock and it was in the center, dead on.
One problem though, if so it would most likely be a new type lathing, (or for just a few years) process (or we would have seen it on more coins) or in the past on occasion???
Or could there have been a guard of some type to cusion that pivot point that has been left off at times?
I agree it would be "very" hard to see on the die itself if seen at all.

[hasfam]

Mmm, interesting. I don't think I've seen that before. I like your theory Jason.
Rock

[mustbebob]

Correct me if I am wrong, but isn't the positioning point of the lathe at the back of the stock? It certainly wouldn't be in the middle of the portion needing to be worked on. This is my opinion only, but I don't think it is a lathe mark as the lathe is used to make the hubs, and not the individual dies. If it were a hub that had these marks, there would be a lot more of these around as the hub had to make numerous master dies, that would have then made the working dies. This has been found on the obverse of 1998 and 1999 cents (very few have been reported) and on the reverse of 2004 cents of which there are 3 known varieties (each a little different location, but still centralized). One 2004 cent with the circle also includes a column bar doubled die. This is another one of those 'how did it happen' scenarios. But since there are different varieties of these, I believe it isn't the lathe that produces these. It most likely is a die related and not hub related issue.

[jcuve]

From what I have read there are a number of lathe operations that file down and reshape various parts of the die. I believe all of them would all be attached to the back (not the front). What I am suggesting isn't so much a lathe mark as some sort of small step somewhere when the die is fit onto or taken off a lathe or maybe from one of the tools that spin around the die which is not supposed to make contact with the die, but briefly does. Thinking as I write, maybe it doesn't have to be during a lath operation but at some point when the die needs to be centered for some reason and something that is not supposed to make contact does make contact accidentally. It just doesn't appear to be random, so I feel it is an external object of some sort that makes taps the die directly in the center. Maybe a more detailed analysis could reveal whether it is done while the die is annealed or later when it is tempered to narrow down the possibilities.

Again, this is all conjecture (and not a theory) as I have no evidence to support my ideas.

POSTSCRIPT: I should add to clarify that there is a section of the book The Error Coin Encyclopedia IV that details the various stages dies go through as they are trimmed down from the hubbing size - those are the lathe operations I am refereeing to, not the earlier procedures where the conical shape is ground onto the die face.

[jpl6332]

During the intial die making process the dies are annealed (heated ) so that they may soften a bit during the impression or squezzing, this is repeated several times until the design is shaped correctly and so called perfection is achieved. During this annealing phase the inner molecular structure of the carbon is stressed, this is of course is where doubled dies are created as we all know. There is another unwanted effect which causes some parts of the die face to heat and cool at different times based on the properties of the "tool steel mixture" , this can cause unwanted pockets of the steel to react a little differently than others on the die face, in other words some areas of the die face could be more brittle than others or soft as the case may be. If this is what happened with these dies it is not inconceivalble that while retooling this area became a tad brittle or soft and caused the unwanted defect....my thoughts on the subject anyway.

[mustbebob]

Although annealing may be an explanation, these dies were all created using the single squeeze method, so annealing does not necessarily take place. I think Jason is on
the right track with something hitting the dies. This has been debated and researched a couple of years ago. This anomaly was also at one time compared to the Wisconsin High/Low leaf varieties as both of those anomalies are circular type gouges like this one. Of course, you can't get the mint to admit to anything, so our educated guesses are the best there is right now. Good conversation though.

[jcuve]

Yes, it has been a good discussion.
I could be wrong, but aren't the dies still annealed before a single squeeze hubbing and then tempered after? I would think they would be. I mention the annealing process as R. Snow had concluded through a electron microscope analysis that those Low and High Leaf dies were struck by something round after the hubbing but before being tempered (hardened). He also suggested it was done on purpose which is unprovable but that is another point.

The die was hit or bumped dead center - somehow, on different occasions (i.e., years) in the same place. I feel it is an accident that periodically occurs and slips past quality control. Bob appears to be right that the Mint is not likely to validate any of these ideas LOL.

It's so nice outside right now...why am on the computer?

[THE PENNY MAN]

WOWSER'S!!!!! that is some information on this MYSTERY coin. Thank you all.

[trails]

Come on guys, its Lincoln's hula-hoop.

Seriously though, I do have a obverse circle on a 1988 Lincoln cent as well as a 1993 and 2004 Lincoln cents with the reverse circle. No one is exactly sure what these circles are, but I believe that they may have something to do with a lathe operation.

BJ Neff

[jpl6332]

Now that I can see the pictures in a clearer light it appears to be some type of registration mark, which would lend credence to the lathe theory.
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