Here's a 1991-D Half Dollar, struck through grease and also with some heavy mechanical doubling (ejection doubling?), particularly at the B and E of "LIBERTY". Question to those that can explain this to the rest of us: Particularly on the 'B' what process causes different parts of the letter to appear to be "pushed" in opposite directions?
I have seen a similar issue on letters and numerals for Broadstruck errors but the Half in question is not Broadstruck
Looking at the coin as a whole, it has some Die wear The coin also has some struck through grease, I wonder if that raised line in the B is an artifact of both, DDD and struck thru.
Interesting effect. The letter B is smeared north-to-south and south-to-north. This may be true of the E as well, although the primary direction of movement is north-to-south. This most closely resembles the form of machine doubling known as "slide doubling". I have noticed that some grease strikes are associated with smearing of the design, so this may have been a contributing factor. Exactly how it contributes is unclear.
I should add that while the letters appear to be "smeared" N-S and/or S-N, this is true only if North is considered to be directly above each letter. Some degree of this effect is evident at nearly all the letters and when looking at the coin as a whole this effect is really in a radial direction from near the center.
A radial pattern of doubling/smearing is inconsistent with machine doubling. Perhaps the entire effect is related to the presence of grease. Again, the etiology is otherwise obscure. I invite you to send me the coin for a possible write-up in Coin World.
Will you consider sending it to Mike Diamond. That would be a great item on Coin World if he decides to do an article.
My article on this half dollar, and other coins afflicted with the same pattern of smear, can now be found in the latest online edition of Coin World, which was released this morning. While it's not a new or rare phenomenon, it has escaped everyone's attention. I call it "grease-mediated radial smear" or "radial smear" for short.
