Tapering/thinning of peripheral devices explained

[willbrooks]

A couple of folks asked me about this study, and so I will post an abridged version of it here for the community. We had a question on the forum here from someone asking about some thin/tapered letters on 1996D cents that he was finding in mint sets. He was convinced the difference in the letters was a new design variety. Despite assuring him that I had seen this on several different dates and on various areas of the periphery, and was therefore either due to an incomplete hubbing, or else over-polishing of the die, he was not convinced and was still insistent that it must be a design variety. So, I got the coins from him and studied them, and then sent them to Ray Parkhurst for him to photograph in 3-D rendering. The results were quite conclusive that, in fact, this effect was indeed caused by over-polishing of the field in that area. 1st and 2nd pics are of the "thinned" coin vs a normal coin of the same date.





Now, in this last image, Ray did an inversion of the image so we are actually seeing what the dies would look like, rather than the coins. Here we have our “smoking gun” as Ray put it. With this incredible technique, we can see that the die near the rim on the coin with the thinned devices is clearly compromised compared to the “normal” die.




I was able to find and photograph a couple of others from different dates with the same effect going on. Here is a 1989 with the same thing.



And here is a 1986 with thinning on ONE.




And here is an example from the coppercoins listings.
http://coppercoins.com/lincoln/diest...&die_state=mds

If you search a lot, you will find these, as well as thinned out FGs, etc.

I am glad this came up as this is a nice precursor to the other study we have just completed, and on which I am still awaiting word.