A fellow metal detector wrists found the coin below. It’s from northern New York state near Lake Champlain. I have found numerous older Canadian tokens and US coins in the area. This coin, he states, is about the size of a nickel and rather thin. He believe it’s not a button. Thanks.
It’s a double sol (1/10th of a livre) of Louis XV of France. They were struck between 1738-1769 with numerous minor stylistic variations and differences in spacing of the lettering. The one sol had the same design, but was smaller (17mm versus 22mm for the two sol).
The reverse should look like this:
They don’t survive well in the ground since they were only .250 fine silver.