Found in Rolls column from Aug. 10, 2015, issue of Coin World:
It may surprise you to learn that I find Proof coins in Kennedy half dollar rolls on a fairly regular basis.
In fact, I have found well more than 100 pieces, with the dates on the coins ranging from 1964 all the way up to 2012.
I have yet to find any dated after 2012, but I suspect that given enough time, later dates will eventually turn up as I continue searching rolls.
Keep in mind that the word “Proof” is used to describe coins that are struck using specially prepared dies and planchets. The word “Proof” refers to a method of manufacture and does not denote the condition of the coin based upon wear.
Most Proof coins that are found in rolls are what collectors would call “impaired Proofs.” Proof coins that I find in rolls are usually just that: impaired.
So, what does that mean?
An impaired Proof coin is one that has condition issues. It is one that may have scratches or problems with its surfaces that would render the coin less than desirable to a collector. An impaired Proof coin may even show signs of circulation and wear.
Proof coins are graded similarly to the ways that we grade other coins. Without going into all the details, you may see normal Proof coins designated in ranges from Proof 60 through Proof 70, with Proof 70 being the grade assigned to a perfect Proof coin. An impaired Proof can be assigned a lesser grade, like Proof 50 or 58.
Most Proof coins that I find would fall into the lesser grade range as described. They are circulated Proofs, and as such, they have some dings and scratches.