I pulled the "Black Beauty" nickel from a roll of '58
Jefferson nickels, which happened to contain ten more "Black Beauties" Although the nickel(s) are actually "Gun Metal" grey they throw off Blue and purple highlights (too difficult for me to capture the shades with the camera).
Pictured below is a side by side obverse of the 1958 Beauty and a 1938 for color comparison.


The '58 and '38 reverse

The '58 "Black Beauty" Obverse

And the reverse
The coins contained in the roll are in various stages of darkening. I don't know if it's the annealing error or not but they are different for sure. Comments anyone?