1965-1969 Kennedy halves were silver clad consisting of 40% silver. I don't have an answer as to why the toning has that appearance. Both are graded by NGC.
The outer layer (the part that would tone) is 80% silver. That's why they are able to tone relatively well. I'm shocked that NGC would slab those. The reverse looks like it was toned/colored at one point, since the gap areas have color incuse.
I appreciate your comments. The look and characteristic of the toning undoubtedly appears different in hand as opposed to looking at a non 3D image. I also believe these coins toned well better than "relatively well".
I have some I want to share but I'll have to wait until after Christmas to open my new camera and see if it takes good coin pics.
here are a couple i found today. i opened about 60 1979 and 1980 proof sets for the first time and found 90% of them toned gold and some with blue/purple/gold/pink rainbow type patterns. and i had never noticed the blue '62 proof nickle either.