Watch List notes:

CYCLADES, Keos. Koressos. Circa 480-470 BC. Trihemitetartemorion (Silver, 6.5 mm, 0.41 g, 3 h). Dolphin left; below, O. Rev. K within incuse square. HGC 6, 585 var. (dolphin right). Papageorgiadou-Banis Series III, 37 var. (dolphin right). Sheedy Series III, 41 var. (dolphin right). Extremely rare with dolphin left. Lightly toned and well centered. Very fine.
Ex Classical Numismatic Group E440, 20 March 2019, 119.