Is this a retained cud? It definitely looks like a die crack from rim to rim...although I could be mistaken for plating issues
Looks like it might be a rim-to-rim crack. The middle of the crack seems less defined than by the outer devices. Is this just a optics thing with the photo?
I'm not 100% convinced it is a rim-to-rim die crack. Part of it looks like a crack or lamination and part of it looks like a plating bubble.
I think it may be a planchet flaw (oxidization) that has started to corrode from underneath and caused the plating to split.
Sorry, but I'm not finding the photos to be particularly helpful this time. What is useful are the two shots of the second A in AMERICA. From one perspective it looks like a crack. From another, lifting of the plating. In the middle is looks like a long blister. Between ONE CENT it looks like a lamination error. In total, it looks like it might be a lamination error with lifting of the copper plate and perhaps a little hydrozincite starting to form under the lifted plating making it appear as a crack. If it is a lamination error, then you might want to stick it into an airtite to keep the zinc rot from really setting in. An interesting coin.
I haven't either, but there's always a first time during a CRH event (or spare change). I've not found a Zincoln lamination error yet either.