On Error Ref, it says that rim restricted design duplication is known on 1994 and 2004 cents. There is a picture of the 1994, but I am wondering where to look on 2004 cents.
Here's the link: http://www.error-ref.com/?s=rim+restricted+design+duplication From what I understand after reading the info, IMO the lettering should be somewhere on the rim. The 2005 cent shown is a different kind of error, A Rim Restricted Second Strike, the lettering is below the rim, not on it. One of the many members with more experience should be able to give you the correct info.
I didn't see that you'd posted the link, so I posted it. The doubling could be in approximately the same place as the 1994, but I don't even know if it's on that side of the coin. The dies could have very well been inverted in 2004.
Thanks for posting the link. After reading the explanation, I'm assuming that it occurs at about the same position as the part of the legend that is duplicated, and it is always from the hammer die. Someone correct me if I'm wrong, but I always thought that the obverse was the hammer die. ~ Chris
On the 2004 cent, the extra letters on on the reverse rim. That makes perfect sense, as all but a few 2004-D cents and all 2004 (P) cents were struck with inverted dies (reverse die as hammer die). Here's an image of said cent:
Chris, beginning in 1992 (first at Denver), the US Mint began a slow transition from the conventional die setup (obverse die as hammer die) to the inverted setup (reverse die as hammer die). The changeover was almost complete by 2002. The old presses were trotted out on rare occasions as late as 2007 (again at Denver). Since then, all business strikes have been struck with the inverted setup. Proofs are still largely struck with the conventional setup.
Perfect!!! I really appreciate your response. I see where you wrote that the collar clash error can be a strong, but not infallible, indicator of specific die setup. I find these errors quite regularly when coin roll hunting and wonder if any are considered rare and worth keeping. I suppose that since the error doesn't indicate *definitively* the die setup, keeping any, say, ultra modern ATB quarters with collar clash present on the obverse rim, would not be worthwhile.