Watch List notes:

William IV, sovereign, 1831, first bust r., nose to second N in BRITANNIAR, rev. crowned shield of arms (S.3829; M.16C), certified and graded by NGC as Mint State 63 Prooflike
A most unusual piece. With prooflike status, it could easily be seen as a proof. Rare in this grade. The highest grade awarded by NGC.

Estimate: 6000 - 8000 GBP