I say post mint. It looks like vice marks on the reverse. It also looks more like it was a complete coin that was flattened, rather than clipped.
Looking at just the obverse I say there is a chance that it could have happened in the mint. Once I saw the file marks/scratches on the reverse I switched my vote over to post-mint damage.
here are my thoughts. The scratch marks seem to be unrelated to the clip due to their orientation. If they were parallel i would agree. They cant be vice marks cause then they would also be on the obverse as a vice has two jaws. Even if one jaw had a cover, to make that mark on the reverse, it would atleast leave marks on the rim of the front. Is it possible that due to the clipped planchet it got stuck in a machine causing a jam and making those marks? Also, I've cut alot of metal in my life and I dont know of any tool or saw that would make such a clean cut. It has no teeth marks, grind marks, ect and is a super clean cut. There is no warping to the coin and the top of the r and s are still intact. The redbook says clips can be straight and the coin is the same thickness through out so it isnt flattened. If you think this is post mint, please come up with a scenario that would support your claim. Im interested.
Post mint. If it were a clip, it should almost bevel toward the clip and the lettering should taper into it. Unless I am cross-eyed, yours has a lip there. That could only come from something scraping/pushing the edge in.
It's an obvious fake. There's no metal flow, no Blakesley effect, and there is a line of wear along the staight edge. This indicates the edge was slightly elevated, which is impossible in a genuine straight clip.
It's BOGUS. It was probably done with a grinding wheel hence all the scrapes on the reverse. Thanks, Bill