Here’s a closer look at the mark on the reverse. I always thought this mark was from rolling out the planchet strip. Or perhaps it was an irregularity in applying the zinc coating. Maybe some other members would like to weigh in on what would cause a mark like this.
Can't compete with some of the originals on here but my reprocessed set developed some great toning over the years.
The MS-67 1943-P coin @robec posted has the same type of marks at the top right wheat ear and PLU on the left. the unproven theory https://www.error-ref.com/accidental-die-abrasion/.
I thought about doing a joke GTG on this one because it’s in a BS (Basement Slabber) slab even though it’s a really nice looking coin.