Greek Caria, Kos, AR Hemiobol, (Silver,0.58 g 8 mm),Circa 500-480 BC. Caria, Kos, AR Hemiobol, (Silver,0.58 g 8 mm),Circa 500-480 BC. Obv: Crab. Rev: Quadripartite incuse square. Ref: SNG Keckman 903;