Far from being a non-color, grey has surprising connotations in
Roman coins were a Greek idea
Rome didn’t have coins until 300 B.C., when the Senate began the system. Before this, the Greek colonies to the South had been using coinage for some time. While they were aware of the coin systems, they didn’t start using coins until they had silver mines.
No living people allowed
At least, that is, until Julius Caesar. During the time of the Roman Republic (and after about 300 B.C.), the only faces that were allowed on coins were gods, allegorical figures, or dead famous people. One good example of this is a coin portrait of Pompeius Magnus (often known as Pompey), made by Quintus Nasidius. Nasidius had a relative who served as a naval officer under Pompey, so he brought attention to his famous relative and Pompey by putting Pompey’s face on a coin.
Coins weren’t big until after beating Carthage
Carthage and Rome did not get along. In 264, both powers got embroiled in a smaller conflict which escalated into a full-fledged war between Carthage and Rome (the largest powers of the time). Then another one. And another one. During the second war, Rome seized control of Carthaginian lands in Spain which contained one thing Rome had never had before: silver mines. With its new source of precious metal, Rome began its coin system.
Coins were political statements
Like the Pompey coin above, many coins were used by the minter to bring prestige to his name and attention to famous relatives. Their names were often written on the reverse side at the bottom of the image. One denarius, featuring the face of Roma (the goddess of the city of Rome), also reads, on the reverse side, C. Metellus (the minter’s name). Image here.
The Romans once made “money bars”
One of the early types of coinage were large bronze bars now known as aes signatum, or ‘struck bronze.’ They were about 6.3 by 3.5 inches and weighed about a kilogram.
Minters were a good beginning government position
The Roman Senate was a difficult body to get into. A senator needed to be male, own property, and have a certain amount of wealth. So, a mint worker could gain prestige, money, and government position all at once.