Yes, the center bottom of the grid is the date. It looks like 766 to me (1766)
The top right part of the grid (and bottom left) is the essayer, considering the date and my books (and what we see) - this looks like a V.
Which sticks well to the Potossi mint (where a P should appear on the top left and bottom right) - maybe we see a bit of it in the bottom right.
The cross side should have on the bottom the date (which I think I see partially), and on the left the mint mark (p), on the right the essayer (V)
Your coin is in a pretty good condition for this type and denomination !
The top right part of the grid (and bottom left) is the essayer, considering the date and my books (and what we see) - this looks like a V.
Which sticks well to the Potossi mint (where a P should appear on the top left and bottom right) - maybe we see a bit of it in the bottom right.
The cross side should have on the bottom the date (which I think I see partially), and on the left the mint mark (p), on the right the essayer (V)
Your coin is in a pretty good condition for this type and denomination !























