Watch List notes:

STUART. James II. 1685-1688. AR Halfcrown (34mm, 6h). Tower (London) mint. Dated 1686. Laureate and draped bust left / Crowned cruciform coats-of-arms around rayed Garter star. Edge: blank. Cf. ESC 494; SCBC 3408. In NGC encapslation 6027342-010, graded Mint Error F 15, double struck, 2nd strike off center.

The missing edge lettering is likely a result of the unusual striking error.