Watch List notes:

CORINTHIA. Corinth. Circa 490-460. Diobol (Silver, 10.5 mm, 0.67 g). Ϙ Head of bridled horse to left. Rev. Δ within an incuse square. BCD Corinth 37. BMC 97. HGC 4, 1881. Rare. Nicely toned and very well-struck on an attractively oblong flan. Good very fine.
From the "Collection sans Pareille" of Ancient Greek Fractions and from the collection of R. Maly, LHS 100, 23 April 2007, 256.