Yes, I remember it now. You can see the struck through error (grease) on the field and on the bust. Not a lot of value for this, but it is added to my educational image files: If it were die damage, the area in question would be raised. As it is, it is sunk into the field.
I am sorry, but I still feel that has to be a defective planchet. I have seen a lot of grease filled minted coins here and not one of them has shown any roughness as is evident on your coin above the date. See the references below. The most dramatic example I have seen is my 1923-S http://www.cointalk.com/t145677/. There is no evidence of any roughness on the entire coin. In fact the coin has very nice luster for a brown Lincoln. http://www.cointalk.com/t145677/ http://www.cointalk.com/t134053/ http://www.cointalk.com/t119479/ http://www.cointalk.com/t81756/ http://www.cointalk.com/t94172/ http://www.cointalk.com/t102738/
I agree. In my opinion that coin was not struck through grease. As you pointed out, grease doesn't leave that kind of roughness. It may be a struck through, but it wasn't grease that it was struck through.
It's most likely struck through "grease". The term "grease" is a catchall term for any kind of gunk that accumulates on the die face. The texture of this gunk is highly variable and is often rough. Compacted "grease" can be hard and brittle. It can break off into irregular flakes. In copper-plated zinc cents, "grease" typically has a smooth texture.
Thanks Mike. Can this "grease" stick to a die and imprint more than one coin with an identical pattern?
Yes, grease can leave an impression on a succession of coins. The impressions can be identical or they can change in size and shape as the grease accumulation grows or shrinks in size.
