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Kleroterion

A kleroterion in the Ancient Agora Museum (Athens)

A large kleroterion at the Ure Museum of Greek Archaeology in Reading

A kleroterion (Ancient Greek: κληρωτήριον) was a randomization device used by the Athenian polis during the period of democracy to select citizens to the boule, to most state offices, to the nomothetai, and to court juries. The kleroterion was a slab of stone incised with rows of slots and with an attached tube. Citizens' tokens—pinakia—were placed in the slots and the tube was filled with different-colored dice. The dice were released one by one, each die corresponding to a row of pinakia. The color of each die determined whether the owners of the pinakia in the corresponding row were selected for seats on the boule or juries.