Just for Newbies, and who ever has more time on their hands then they know what to do with, I thought that a review of machine doubling (aka Strike doubling, and other names) would be in order. Machine/Strike doubling happens when the die (usually the upper or hammer die) is placed into the machine and is not tightened completely. As a result of this loose fitting, the die is able to rotate, that is, move slightly each time that it strikes a coin. Because of this motion, the die moves or 'scrapes' along the (now) coin and slightly (ever so slightly) moves the die across the face of the coin. The result is that the struck devices on the coin are 'moved' that is, they are shoved in one direction or another. The net result is that there appears to be another image of the (usually) lettering on the coin. This is not to be confused with a doubled die. In doubled die, the die has been 'impressed' with the design elements and then reheated, for the impression to be made again. (The purpose of this is to enhance, or improve the design on the die.) With a doubled die (please note: it is a doubleD die, NOT a double die. The die has been doubled.) The doubled design is the same height as that on the original, or first image. With Strike doubling, the secondary image is usually very slight, that is, it is very close to the original image. With a doubleD die, the secondary image may be close to the first, as with the 1995 Lincoln cent, where the primary doubling is on LIBERTY. Or more distance, as with the 1955 doubleD die cent's date. And, rarely, extreme separation, as with the 1969 doubleD die cent. True doubled dies are scarce, and usually of very low mintages. The one, popular, exception is the 1995 doubled die cent, which has an estimated mintage of from 600,000 to 1 million pieces. Despite the large mintage, it still sells for a fair premium in uncirculated, but is not worth a great deal in circulated condition. The machine/strike doubled coin is considered by most collectors to be damage to the coin and therefore, not worth as much as a coin without the strike doubling. Some collectors, purists, coinsider it damage and will only pay less for such a piece. I have been criticized for saying that coins that have machine/strike doubling have "no added value". I have stated this not because it is just my opinion, but also that of the 'experts' in the field of error coins. they have taught me a great deal, and the first thing that I learned was: strike doubling has no added value. If you, the collector, decide that it had a value to you, then go for it, pay a premium if you like. That is the joy of coin collecting, we can each collect what we like. But, don't expect to mke a profit on the coin, unless you find a like minded individual. Other 'doubling' (if you are interested) may be die erosion, Longacre Doubling, or re-punching of the date or devices. If there is interest I will continue this discussion. Thank you.
Very good post - a very thorough examination of MDD. I think it would be beneficial to continue the series with discussions of DDD, Longacre, etc., for those unfamiliar with the terms. I know many collectors see these common (and essentially worthless) errors, and think they have discovered some great rarity worth millions.
physics: Thank you for your comments, and I will continue the discussion. Very soon. And thanks for the nominations. [only 6 more and I have a chance for thread of the week!]
Informative post, and information any coin searching should not forget. I still get caught up on truee doubling. .. but if i ever do come across a real doubled die ... it should clear the confusion up for me lol
This was a good post... Just one question, how exactly is a doubleD die made? Wouldn't somebody look at the die before casting many many duplicates of the same thing? One would think that the die would be examined very closely, so that there are no errors. And how would I tell machine doubling from a doubled die, if I had a coin in my hand with doubling on it?
Nice info. I know I look at a lot of coins and at first glance think I have something. Under closer inspection, back in the junk pile. Now how about a step by step on doubled dies.
I still don't see a difference, I mean I can see some are stronger doubled than others, but how I am supposed to tell if it is strike doubling or a doubled die?
Thank you and yes continue on...I was using double die instead of doubled die. I just posted what I think to be a doubled die...will you please look at it? Thanks
Strike doubling has a shelf look to it, whereas doubled die edges are rounded and look for a split in the serif.
Huh? I'm just really confused, errors are not my cup of tea... Although I would like to learn, I will look at those sites again, and try to find some examples of both.
"Huh?" I like that. That's just what my kids said when I would explain things to them. I was never any good at it.
It is not just you, I am checking out this site (http://www.coin-gallery.com/cgstanton3.htm) and I am confused out of my mind Trust me I know the feeling, when I try to explain things to my family about coins... SHEESH!