If you want to do an experiment on plate shifting, you need steel cents & naval jelly. Soak the cents for a day or two,or maybe longer, the zinc coating will start shifting giving the coin a doubling appearance. I accidently came upon this trying to remove some rust from a steelie.. Once you try it you'll be able to identify it in the future. I have sent some of these out to be attributed. They came back as being odd/different, but definatly post mint. They were never told about the naval jelly. Now they know...
I don't understand what you mean about expermental please clear that up it does not computeKiss Jazzcoins Joe
It's a form of die deterioration doubling. The plating hasn't split. And there is no such thing as "plate shift doubling".
Just hypothesizing, maybe everyone meant, "Plate Split Doubling(?)," a term (I believe, but may be wrong) that Ken Potter coined, or at least is on a website of his, discussing other forms of doubling. Of course this doesn't appear to be plate split doubling but as you stated, DDD. I feel like this form of DDD is harder to diagnose as it almost looks like MD or a problem with the plating, as opposed to say the DDD exhibited on the '55 PMDD. Jason
I've used the term "split-line doubling" when referring to split plating, but I'm not dogmatic on its use. The DDD in zinc cents is often rather peculiar-looking. Zinc is rather hard on the dies, even though it's a soft metal. This may be due to unusual visco-elastic properties, i.e., zinc acts has a hard metal when subjected to enormous pressure at high speed.
There is no mechanism by which plating can "shift". The incuse doubling is a form of die deterioration doubling. It is most exaggerated where letters extend into "swollen" areas of the coin caused by the die face sinking in.
You are the one that used that term nobody else did.plate shift doubling I didn't use that terminology. JC
Mike a question, while what you say is a perfect answer, Mike a question, while what you say is a perfect answer and I agree on this particular coin, but there was some extra thickness to 1992 P&D Lincoln's that I have noticed often - I was never sure if Neff or anybody else went into detail regarding this but they were much thicker that the year before or after. Plus it may be nothing but I do not remember seeing anything about it in print. Have you notice this and do you have any thoughts regarding it??? Thanks, Ben
