Watch List notes:

BITHYNIA, Kalchedon. Circa 260s BC. AR Tetradrachm (29mm, 16.72 g, 12h). In the types of Lysimachos of Thrace. Diademed head of the deified Alexander right, with horn of Ammon / Athena Nikephoros seated left, arm resting on shield, spear in background; monogram to inner left, grain ear in exergue. Marinescu Issue 4, 10 (O7/R10); Türkoğlu LO2a; HGC 7, 523; SNG BM Black Sea 131 (same obv. die); Meydancikkale 2706 (same dies). Good VF, toned, a few marks, traces of horn silver on obverse, slight die shift on reverse. Very rare, only nine noted by Marinescu, four in CoinArchives.