Found this in my rolls today - Not your typical blacking due to burying Hard to get true colors due to the LED lighting.
Improper annealing is tougher to prove on nickels. If the edge has the same toning as the surfaces, then it's environmental damage. If the edge appears to look like the normal coloration, then it might be a misannealed piece. (I learned that identification tip from a @Fred Weinberg post)
Thanks for the info: The edge is not quite as dark as the fields but has some discoloration - I did see one 1958 that showed the edge and it was a bit darker than a normal nickel. I thought they were worth more though, I saw a 1958 certified one on Ebay for $43 Not really enough to get it certified.
Based on the photos, that's not a mis-annealed nickel. Just toned a bit. And, the genuine ones, mostly dated 1959 and 1958, are only worth $20 or so. The $43 is a high asking price, and has nothing to do with what they're really worth, imo.