Watch List notes:

CRETE. Kydonia. Circa 450-330 BC. Obol (Silver, 10 mm, 0.91 g). Sea turtle swimming upwards; to left, crescent with points outward; to right, pellet. Rev. Skew-pattern incuse square divided into five compartments. E.S.G. Robinson, Pseudaeginetica, NC 1928, p. 177, 14 (this coin). Apparently very rare. Clear, well-centered and lightly toned. About extremely fine.
From the "Collection sans Pareille" of Ancient Greek Fractions, ex Münzen und Medailen FPL 527, November/December 1989, 58 and from the collection of G. Philipsen, J. Hirsch XXV, 29 November 1909, 1030.