BITHYNIA. Kalchedon. Circa 340-320 BC. Drachm or siglos. Obv: KAΛX Bull standing to left on a grain ear. Rev. Quadripartite incuse square in the form of 'mill sail'. HGC 7, 517. SNG BM Black Sea 112.
Weight: 5.38 g. Diameter: 17 mm.