Does anyone know the significance of the counterstamp on my 1806 British Third-Guinea?(7 shillings).
It seems to have an 'S' over a horse which is running right, over a numeral '5' on its side, with a dot below. All in a small ornate heart-shaped cartouche.
Not just a casual stamp, I believe, but, in view of the amount of detail on so small a stamp, an official one.


