Here is my new 1988 cent with reverse cud. It was found at the Willimantic coin show last weekend. Thanks for letting me share. Please post 'em if you got 'em.
I would like to see a better close-up of the break on the rim. It's clear enough to see in the field, but I don't see how it has affected the rim. Chris
Here are some close-up photos of the reverse cud at the rim. The photos are shot through a 30x microscope using white light illumination. The 3D image viewing through the binocular microscope is really cool. Obviously, you miss out on the 3D image in this photograph. (1) I am curious about what you are inspecting on this coin at the rim (so please let me know). (2) I am surprised you didn't ask to see more detail regarding the die file marks below the Lincoln monument. This 1988 reverse cud is unlisted in The Cud Book by Sam Thurman & Arnold Margolis.
I may be wrong, but I think this is some kind of PMD. What confuses me is that a break this massive should show more zinc than copper. Chris
There can be no doubt that this is a cud (marginal die break). The design rim is gone. What you're interpeting as the design rim is persistence of the proto-rim that was present on the unstruck planchet.