Hemidrachm (?) (Coin) Depicting a Shield

From the Art Institute of Chicago record

The use of coins as a form of money was invented in western Asia Minor in the early 7th century BCE. At the time this coin was struck, Greece was made up of separate city-states that issued their own currency. Made of gold, silver, bronze, and electrum (a gold-silver alloy), coins were literally worth their weight, but their value varied according to the percentage of their precious metal content. Occasionally a city needed more money than it had in reserves. By reducing the amount of precious metal and substituting a base metal, a coin could be produced of the same weight but no longer of the same value. Some currency was only honored within its own city walls, but trustworthy money encouraged trade. Athens had the biggest economy, and its coin became the standard in the Greek world. The population was largely illiterate, but it could identify the place of origin of a coin by its imagery. Many of these images referred to myths that were associated with the history of the community and thus were well known to the populace from religious ceremonies and theatrical entertainment. The story of a city’s founding, a local hero, the city’s guardian deity, and even the reason for the city’s wealth were subjects for a coin’s insignia. The distinctive shield shown on the front (obverse) of this coin was particular to the Theban army. It remained a symbol of the city for centuries until 335 BCE, when the city was razed for opposing Alexander the Great, and its citizens, who used this coinage, were enslaved. The back (reverse) of this coin depicts a volute krater in an incuse square frame.