Great Britain
George III Proof Sixpence 1787, ESC-1628(R4), S-3748, PR55 NGC. Struck on a heavy flan weighing 4,64 gm. No hearts in Hanoverian shield, edge plain. This is a mishandled Proof, yet with attractive gray toning and a strong portrait. Truly a rare type.
Estimate: 800-1000 USD