Hard to be specific with the photos provided and grading is impossible but here are important facts that are relevent to your inquiry. Kennedy half dollars are generally abundant and common and readily available in high grades. I dont see any in the photos but only 1964 Kennedy half dollars are 90% silver. 1965-1970 are 40% silver and 1971 to date have no silver. The silver content is where most of the value lies in these types with a few exceptions for very exceptional specimens. They generally dont circulate so there are many very nice examples available for all dates. 1976 was a one off date celebrating Americas Bicentennial. Read the pages for specifics and look for a mimtmark where applicable. For simple silver value, scroll down the respective page and you will see the minimum silver value content for that coin regardless of condition. That would be your minimum value for that silver type coin.
N#943
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