Quick note: both reverse are are typical and have no abnormalities. This buffalo nickel has a crack in the face and a chip taken out? Is this post mint damage or what could this be? And second, this 64 kennedy has odd "toning" lines that make the whole coin look striped. Is this just tone or is it residue (it doesnt appear elevated at all). If it is toning do you know what caused it?
Nickel issue is called a Lamination Error http://www.error-ref.com/lamination-error-loss-before-strke/ and http://www.error-ref.com/lamination-loss-after-strike/ The half is not a Mint Error. Residue is a good explanation
Typically what is sometimes called bag toning or textile toning has a crosshatched pattern similar to what you'll see here - https://www.google.ca/imgres?imgurl...LHXAhXK5SYKHXAlC8EQMwg9KAAwAA&iact=mrc&uact=8 https://www.google.ca/imgres?imgurl...LHXAhXK5SYKHXAlC8EQMwg_KAIwAg&iact=mrc&uact=8 https://www.google.ca/imgres?imgurl...LHXAhXK5SYKHXAlC8EQMwheKBcwFw&iact=mrc&uact=8 But toning can come in all kinds of patterns and the pattern can often derive from whatever it is that coin happens to be against during the time period. What exactly caused that specific pattern ? I have no idea but it could have been almost anything.
The striped pattern almost looks like fiber reinforced tape. It often leaves residue in that pattern.