Think the question I need to ask is.....What Unertl rings are you referring to? Looking at the rest of the posts here it appears that everyone is responding in regards to the 8X USMC SNIPER WW2 era scope rings/elevation, windage turrets.
What throws me is in the Thread headliner you mention "Blackening" then in the subject you mention Anodizing.
My first thought when reading it was that you were referring to the M40A1 Unertl mounts that were steel and were finished in Black Oxide.
But when you referred to having them Anodized assumed you were talking about the 8X.
My 8X mounts/turrets have faded to a brownish color. I personally like the worn look.