A Sheep's Ankle Bone, Thrown to Read the Future

Astragaloi, the ankle bones of sheep or goats, were used across the ancient Greek and wider Mediterranean world both as ordinary children's game pieces and, cast in sets and read according to the combination of sides on which they landed, as instruments of divination, a practice modern scholarship terms astragalomancy. Because the bone is naturally irregular, roughly rectangular but distinctly asymmetric, it can land in four recognisably different resting positions rather than the two a coin offers, which gave diviners a richer, more finely graded set of possible outcomes to interpret from a single throw than a simple binary lot could provide.

Halliday's classic study of Greek divination situates astragalomancy among a wider family of Greek lot casting practices, cleromancy in the broad sense, and records specific oracular sites where astragaloi divination was formally practised, including sanctuaries associated with Heracles, where inscribed tables survive listing which combination of thrown bones corresponded to which oracular response, giving modern scholars an unusually direct, textually documented window into exactly how this particular form of divination actually operated in practice.