I have this coin with a doubled die you can see on the last column and the middle one too. Same on the date
This looks like mechanical doubling where the dies become worn out from coins being ejected. but I'm not going to say it is for sure from just the images
You have a classic example of DDD - Die Deterioration Doubling. Considered worthless doubling and has nothing to do with a true Doubled Die variety. Here is an excellent reference found over at the Error-ref website - It even shows a 1989 Cent http://www.error-ref.com/die-deterioration-doubling-incuse/
Very informative reference material. I would like to know though, how does DDD actually happen? Sure it's deterioration of the die. But, how does this actually physically happen to the coin as it's being pressed, just because the die has deteriorated? My only logical guess would be that a worn die causes the coin stock to be a bit loosely fit inside the pressing mechanism. That is only my uneducated minting guess though. One thing for sure, the pennies minted since 82' are terrible. Was the mint really trying to make biodegradable coins starting with the penny in 82'? Since I've been looking over my change closely over the past several months, I noticed almost all 82' and newer pennies are not holding up well at all. At the same time I'm getting a lot of pre-82' pennies that are in very good shape compared to the 82' and newer. It disgusts me actually that pennies seem to be manufactured with biodegradable material. Just like when I found that my 94' Mercedes roadster was manufactured with biodegradable wiring. Pathetic! Just wondering when the mint is going to start making all coins with a zinc core.
In a very brief description. The die is a piece of metal. The planchet is a piece of metal. The die slams down on hundreds and thousands of these new pieces per minute. The die's detail - 90 degree angles for the words ,etc - the edges start Deteriorating .. and are no longer 90 degrees. They start elongating, wearing more and more and more as metal is slammed against metal. Keep this in mind. The die's job is not to only Form Metal, but it has to MOVE metal around to fill in the spaces, the designs and everything. So it's not like stamping a metal into a curve. It squishes the metal so the metal Flows to areas of lower resistance which are the design details. So you have metal flowing by sheer pressure and speed which wear away at the die's delicate and small design characteristics. Remember the US MInt makes coinage for commerce. to be (a) identified as money; (b) make as FAST as possible, and (c) "quantity" is FAR more important than "quality". But even as the die deteriorates the coins are still fully recognized as money for cashiers, vending machines ,etc so it serves their PRIMARY purpose.
Good information but you forgot to mention that some of a dies detoration comes from coins being ejected out of them. This is why usually mechanical doubling is only on one side of the letters and numbers. Trust me , after I lost nearly a million dollars or more in 1983 by taking a huge amount of doubled dies back to the bank thinking they were only MD coins I have learned all I could since them about how to tell the differences between MD and the real Doubled Dies.
To clarify your post, die deterioration doubling and mechanical doubling are different. MD can occur on a new die as well as an old die. It's caused by a die being loose in the fixture and moving slightly as it strikes the coin. With multiple strikes per second and tons of pressure, it's easy to understand why a die may become loose during production. @Clawcoins has a nice explanation above for DDD. Generally, as metal flows into a die, it doesn't like sharp edges. Over the course of tens of thousands of strikes, the edges began to wear away. Notice on many DDDs that the doubling is on the the sides of the letters next to the rim. This is the direction of metal flow in this part of the coin. Towards the rim. So this is where you would expect the metal erosion. So ejecting the coin from the die chamber has no real effect on MD and DDD. Here is a reference that explains MD. http://www.doubleddie.com/144822.html And here is one for DDD http://www.doubleddie.com/144843 Hope this helps
You would think that before someone tries to correct others they would learn about error coins first. Yes it is a well known fact that what I said Is true . Ejection from the dies causes the dies to be damaged and usually only on one side of the letters and numbers. Regular die detoration doubling usually is a even wear and shows on both sides of the details on the coins. If anyone don't believe it just google " die ejection doubling " and see for yourself.
I’m not an error collector but I believe ejection doubling is when the coin is forced against one of the dies as it is being forcefully ejected, leaving a partial imprint. It doesn’t seem to have anything to do with damaging the die. I could be wrong but that’s the way I understand it.
