Great find! A photo of both sides would help too to grade it, if you want to determine approximate grade and value.
Depending upon the condition and if it is a type 1 or type 2 coin, will determine if it is worth more than a $1 or not.
A proof is a manufacturing process. More info here:
http://www.usmint.gov/about_the_min...tion=grading
Info on type 1 and 2 coins:
http://www.bakercoins.net/learn/art...sba/sba.html
















