Great Britain
George IV Proof 1/2 Crown 1821 PR67 PCGS, Royal mint, KM676, S-3807 (omitted in proof). The single finest graded specimen by either PCGS or NGC (it is the finest by a full 2 grades at PCGS, with only one PR66 at NGC). Wonderful subtle blue hues in the fields, combined with its exceptional state of preservation, give this coin a delicate beauty rarely rivaled. A true gem, the equal of which one is unlikely to encounter again.
Estimate: 8000-10000 USD