Types

• Types of coins in the Roman monetary system were the as (made of bronze), the sestertius (also made of bronze), a silver coin called a denarius and, a gold coin called an aureus.
  
  

Relative Values

• The as was the base unit of Roman currency. A sestertius was worth four asses, and a denarius was worth 16 asses. The aureus was the most valuable by far, worth 25 denarii.
  
  

Actual Values

• At the time of Emperor Hadrian's rule, a half of a denarius (or two sesterces) would have been the typical cost for a small bag of wheat. At the same time, the average annual salary for a Roman soldier would have been over 200 denarii.
  
  

Pricing Units

• In early imperial Rome, sesterces were most often used to establish a price. Later on, in the fourth century and after, an item would more likely have been priced in denarii.
  
  

Coins as Propaganda

• Roman coins generally depicted the emperor ruling when they were minted. Emperors also endeavored to depict war victories and other achievements of their tenures on their coinage.
  
  

Fun Fact

• After the death of the emperor Caligula, the Roman Senate recalled all coins with his likeness from circulation to be melted down, making coins depicting Caligula a rarity today.