WOW, just WOW!!
Dave you truly have found the treasure of a lifetime, as I stated previously, take care and find an expert that can evaluate the coin in its current condition. It may be worth WAY more than you think due to its rarity. Please do not be quick to sell it until you have explored all the possibilities. At the right coin auction it may bring $$ beyond your wildest imagination.
This was so good a find..If you get a call from the White House to invite you and your coin to a Rose Garden party..I wouldn't be supprised. Congrats.
Bonesquat is right. You did barely nick it right under the last "A" in America. Or as he said maybe a rock or something else did. That coin has to have been buried at least 200 years. If not it would be much more worn out. That tiny nick would not have a different color of silver if it wasnt recent...Excellent find and gives me hope in this area...