Bithynia, Kalchedon, AR Hemidrachm c.400-350 B.C.
12.5mm, 2.39gm.
Obv: KA above bull standing left, corn-ear below.
Rx: Granulated mill-sail incuse.
Cf. SG 3739.
Kalchedon's sister-city across the Hellespont, Byzantion, struck identical silver coins showing a cow rather than a bull.