http://agathe.gr/democracy/the_athenian_army.html
The Athenian Army From the very beginning, the Athenians were compelled to fight for their new democracy. Their dramatic victories over the Boiotians and Chalkidians in 506 B.C. led many to attribute Athenian ... On one side a piece of armor is shown: a helmet, breastplate, shield, or greave, and on the other side, the letter Α (alpha), Γ (gamma), or Δ (delta). These tokens might have been used as exchanges for state-owned armor.
