1971-S Lincoln Cent. Best I can do with the lens I have... BTW: The mint mark is double as well. The Liberty looks normal though the doubling could be worn away.
Ron, it appears to be machine doubling due to the flattened appearance. That the mint mark also shows similar, it reinforces the idea since the mint mark was punched into the die separately in this year, and the odds of both being truly doubled would be extreme. Jim
Jim, what is the difference between machine and die doubling beside the uniqueness and value? I'll try to get a closer look, but if it's a flat step than it's machine doubling correct?
Machine doubling is considered damage. Here's an interesting little reference/explanation. http://www.coingalaxy.com/coininfo/doubling.html
Excellent article Merc! Thank You Sir! Yeap I pretty sure it's a MDD. If a die had this issue there would certainly be run on them, and I saw none in the published errors. Makes a lot of since with the mint mark not being doubled on a true '71 DDO since the main hub did not have a mint mark on them. I'm assuming they would have restruck the mint mark by hand to bring the depth back up. A little OT, but (My assumptions) Philly makes the dies from master hubs without mint marks so they can be shared and added by the SF and Denver mints. Explains no D's if the philly made no pennies that year. Why add them if it's not necessary I say...
Before the time of single squeeze working die formation, and the date for that varies according to denomination and source, the practice was to press the hub die and the working die together at least 2 times, and there had to be annealing and preparation done between each time to soften the working die before the next press. The dies have tabs so that they should "always" line up correctly, but sometimes they don't, and a second press is not exactly into the first impression, so you have a doubled image on the working die http://www.coinresource.com/articles/doubled_dies.htm describes the different types of doubling that can be produced as there are also doubling from using different hub dies for the 2nd strike, and one can be distorted , a slightly different design or a completely different design hub producing such coins as the 1960D/D DDO where a large date die was used for one impression and a small date die for the other. Doubled dies from single squeeze production should be impossible, but they aren't and many mechanisms have been proposed to explain them. I am sure others can add or subtract from my answers. Machine doubling is not due to the die being doubled, but mainly from malfunction of the die holders, to hold and align the dies correctly, so in the process of striking, there is movement other than vertical that can create the damage by affecting the details of the coin. http://koinpro.tripod.com/Articles/OtherFormsOfDoubling.htm and this url describes them well. Jim
Awesome Jim! Thank You so much. I truly love this kind of technical literature, along with mint history - it makes my day. Thanks Again...
It's already been mentioned but its buried in text. For Lincoln Cents up to 1990, if the mint mark is doubled the same as the date, regardless of the degree or type of doubling, then its machine doubling.
Dang, you would think MDD would be worth more than it is? Being random in all, the odds of hitting one this nice is worse than finding a 95 DDO? Or close...
Actually not I have gone through original bags of 1970-S and 1968-S cents and about 5% were MDD. For some reason, the presses were not supervised as well or they were badly worn. I will be doing a bag of 1969-S cents as soon as the old timer finds them in his vault , and I expect the same ratio. There are threads on my 70-s and 68-S adventures. Jim
