Watch List notes:

EUBOIA. Eretria. Circa 500-465 BC. Obol (Silver, 9 mm, 0.52 g, 6 h), struck on a thinner, broader flan. Bull's head facing. Rev. Octopus with body above and eight arms; all within an incuse square. Cf. BCD Euboia 334 (but here with the bull's left ear turned downwards and a smaller octopus). SNG Copenhagen. Attractive, boldly struck and with a dark patina. About extremely fine.
From the "Collection sans Pareille" of Ancient Greek Fractions and from the Collection of L. Mildenberg, ex Rosenberg, 11 June 1932, 408.