Great Britain. Proof Halfcrown, 1831. S.3834; ESC-657; KM-714.1. William IV. Plain edge Proof. Obverse portrait of King right by Wyon. Reverse, crowned shield in mantle. Deep navy blue tone over frosted portrait and mirror fields. Very desirable. PCGS graded Proof 63. Estimated Value $4,000 - 4,500