Hi Guys, I have a 1966 "United States Special Mint Set" and Yesterday, when I was giving a look at the coins, I noticed that the Kennedy Half had some doubling on reverse. I know this can be a "Machine Doubling" on reverse, but when I take a look at the obverse this is a "mirrored proof like". So, how can the obverse be too good and the reverse can has "MD"?? I ask it because the Machine Doubling is a consequence of a Worn Die. Isn't?? I researched on the Variety Vista and cannot be sure if this might be a Variant (DDR-002 maybe). The photos, specially the "S" in "STATES" could suggest Doubled Die on the reverse, but after a lot of Threads with frustrations, I really don't believe this case could be anything like that. Tell me you Experts, what do you think off this?? Any comments are welcome and will be appreciated. Thanks, Walter
Not as I understand it. It's a machine hiccup, not a die state change. https://www.error-ref.com/machine-doubling/
Ok, thanks @-jeffB. I'm wrong again. I thought this MD only occur on coins minted by a Worn Die, like this 1973 D Nickel.
Yes, MD does mostly occur on worn dies, but it is also usually the wearing out of the parts that hold the dies in place. IE machine doubling.
MD (machine doubling) and DDD (die deterioration doubling) are two totally different things, and show two different appearances on the struck coin.
