Watch List notes:

MACEDON, Kings of, Demetrios I Poliorketes, (306-283 B.C.), silver tetradrachm, Tarsos Mint, (struck c.298-295 B.C.), (17.03 g), obv. Nike standing left on prow of galley left, blowing trumpet and cradling stylis, rev. **BAS ILEW-S* below, **DHMHTRIOU* to right, Poseidon Pelagaios standing left, throwing trident, chlamys over left arm, trace of monogram to left, X to right, (cf.S.6762, Newell 36 [p.49, not illustrated, only known example found at Sardes], [obv die LVII], SNG Alpha Bank -, SNG Munich 1042 -, SNG Saroglos -). Double struck on the reverse, nearly very fine and excessively rare.

The double striking on the reverse makes Poseidon have three legs.
Ex Triton XI, lot 128, the Dr. Lamar Payne Collection. Previously Triton VIII, lot 181, with tickets and Spink & Son, London on December 18, 1992 with Spink ticket.