The one at 6 o'clock looks good.
Is the color uniform all the way around the outside
edge of the rim ? Should be slightly darker than both the obverse
and reverse. Also, both the obv. and rev. colors should be uniform.
Yes, they should be a dark gunmetal gray color. They have a certain hue
about them also. The color goes all the way through the coin/planchet.
I always check for any small nicks,gouges or scratches etc. to see if the color runs deep into them. I have purposely scratched up darker nickels just to check the color underneath. More times than not (many more) the nickels are just darker from environmental damage etc.
Tough coin to attribute properly without damaging it. Unless they now use a metal analyzer.