Tetartemorion

Mykalessos, a small Boeotian town near the coast, was the site of one of the most savage atrocities of the Peloponnesian War — in 413 BC, Thracian mercenaries en route to Sicily sacked the city and massacred its population, including children in their schoolrooms. That the town recovered sufficiently to strike its own silver coinage within a generation is itself remarkable. At 0.22g, the tetartemorion was the smallest practical unit of ancient Greek silver coinage, fractional currency for the most granular commercial transactions a local economy could produce.