LESBOS. Uncertain mint. Circa 478-460 BC. Hemiobol (Silver, 7 mm, 0.33 g, 11 h). Confronted heads of two boars. Rev. Head of board to right within incuse square. HGC 6, -. Klein -. Rosen 545. SNG Copenhagen -. SNG von Aulock -. Very rare. Very fine.
The interesting thing about this issue, which also includes other billon denominations, is that the two heads on the obverse are arranged in a way that makes the type into a single facing head!