Did some exploring along the Mohawk River today with the ATpro. Just when I was fed up with all the wheat pennies my first colonial silver popped up! I'll spare you the wheat penny pics. The coin is very worn and I wish it had at least a trace of the date.
JM,
Your coin was most likely minted between 1759 and 1808; during the reign of Carlos III (to 1789) or IV; the "CA" appearing on your coin.
Don.......