PaulS.

Hello, Each error is inspected by our error expert. What you describe is something that is commonly seen on 40% silver Kennedy half dollars, and would not be considered an error. Paul

Mechanical errors are quite rare, but NGC grades millions of coins a year, so some mistakes do happen. We correct Mechanical Errors and return them as quickly as possible. I apologize for the inconvenience! Paul

Hello, Neat find! Unfortunately, it's a bit too minor to note on the holder. Paul

Both of these coins are simply damaged. Paul

Sorry, we are unable to provide grade estimates from photos. Paul

This is post-mint damage, sorry. Paul

Hello, This design was struck as a pattern in 1977. However, none were actually released. This is likely some sort of copy or tribute coin. Paul

Unfortunately, this is an older small-sized label and is now retired. Paul

Actual auction results, like from Heritage, are always a good option.

Hello, Unfortunately, NGC is not able to recognize all varieties from every country. There are simply too many to do. This would definitely fall into the too minor to recognize camp. Paul

No, sorry. It would lose the designation. Paul

This looks to be heat damaged, sorry. Paul

NGC backs up its service with the NGC Guarantee of authenticity and grade. If an expensive coin like that is not in an NGC (or other reputable TPG's) holder, there is likely a reason for it. Paul

No, sorry. LIBERTY is heavily doubled on examples of this variety. Paul

Hello, Please call Customer Service and ask for the Registry team. 1-800-NGC-COIN Paul