Watch List notes:

George IV, proof shilling, 1821, laureate head left, rev. crowned, ornately garnished shield, reeded edge (S.3810; ESC.2397), certified and graded by NGC as Proof-64, rich grey toning, bold strike as expected, very rare, from the seldom seen proof set of this coronation year, precise mintage unknown
Two others graded as Proof-64 by NGC, four graded higher.

Estimate: 1500 - 1800 GBP