Kalchedon AR Drachm, c. 357-340 BC Kalchedon , Bithynia. AR Drachm (15 mm, 3.78 g), c. 386-340 BC. Obv. KAΛX, bull standing left on ear of corn, kerykeion and monogram before. Rev. Quadratum incusum filled with dots. SNG BM 104. Rec. Gén. p. 292, 15