Watch List notes:

KINGS OF MACEDON. Alexander III 'the Great', 336-323 BC. Tetradrachm (Silver, 26 mm, 16.93 g, 5 h), struck during the reign of Philip III by the Regent Antipater, Pella, c. 323-317. Head of youthful Herakles in lion's skin headdress to right. Rev. ΑΛΕΞΑΝΔΡΟΥ Zeus seated to left on throne, holding eagle on his outstretched right hand and long scepter in his left; in field to left, helmet; below throne, AΣ. Price 216. Clear and of attractive style. Obverse slightly off center and with graffito A on the reverse, otherwise, very fine.
The style of the letter A of the graffito, with the curved horizontal line, can be dated to the first half of the 3rd century and was added to the coin some decades after it was struck.