Kings of Thrace (Odrysian) Sparadokos (ca 450-440 BC) AR Diobol (Silver, 1.28g, 10mm) - slightly porous
Obv: ΣΠA, Forepart of horse left.
Rev: Eagle flying left, holding serpent in beak; all within incuse square.
Ref: SNG Copenhagen 1065; HGC 3.2, 1671.