I recently picked up a E123 American Caramel card with a Capitol Candy instead of the usual series of 120 or series of 80 (or blank) backs. I don't see anything on back variations in the gallery or on Troy Kirk's site that mentions back variations. Is this back rare? Are there other rare backs?
And while this is probably known, it appears that the blank backs are actually series 80 or series 120 cards that have the back and front separated. I have a few that are still barely attached - and the original owner claims it was moisture that caused the separation (although Troy's site mentions these are frequently soaked so maybe its one of the print runs that had paper issue, and not every print run).
Any information out there on the back variations?