Watch List notes:

Tobago, three halfpence, ca. 1798, incuse TB/o countermark on a French Cayenne copper 2 sous, 1789-A. Vlack-442; Prid-4; KM-5. 1.90 grams. The host coin (French Cayenne as opposed to a colonial crowned-C) indicates that the countermark is TB with o added later to fraudulently increase the value of a 1-1/2d "black dogg" to that of a 2-1/4d stampee type (per Pridmore), this example with very bold and deep full countermark (XF) and fully detailed host (Fine), with traces of lighter original color.
($100-150)