The Sesterce is a common medium-valued coin of the Roman monetary system. It was in use during the Roman Republic and much of the Roman Empire.

Definition and features of this ancient coin

It is the main Roman monetary unit, originally the Sesterce was a small agent coin that had Roma represented : the allegorical goddess of Rome as well as the Dioscuri (the sons of Zeus).

It gradually developed into a large copper-alloy coin. It generally weighed between 20 and 25 grams and had a diameter of around 30 millimetres.

It was the most common currency in the Roman monetary system, and was therefore the most widely circulated. Indeed, large quantities of Sestertii have been found in all four corners of the Roman Empire, and even as far away as India. 

What's more, the Sesterce was considered to be the most common Roman currency, with which the Romans paid for everyday transactions. 

Wages and services were paid in Sesterce, as were taxes. In ancient Rome, fortunes were expressed in Sestertii.

It should also be noted that this was not the only currency in the Roman monetary system; in fact, the Sesterce was halfway through the system. There were also silver coins: denarii and gold coins called aurei (plural of aureus, which is a Roman gold coin). For example, a gold coin (an aureus) was worth 100 sesterces, while a silver denarius cost 4 sesterces.

Sesterces at the heart of everyday exchanges and transactions

We know today from historical sources* what you could buy with sesterces on the Pompeii market:

* ½ kilo of wheat for ½ Sesterce
* 1 litre of wine for 1 Sesterce
* A tunic for 15 Sesterces

If we take the example of Roman salaries in the first half of the first century BC, a Roman labourer earned 1 Sesterce per day, a schoolmaster earned 2 Sesterces per month per pupil and a legionary earned 2.5 Sesterces per day.

Roman historians such as Seneca and Tacitus tell us about some of the fortunes of the time: "Cn. Lentulus Augur, the richest man known, before his freedmen made him look poor, had up to four hundred million Sesterces in his coffers"(Seneca, On Benefits, Book II, 27).

Cnaeus Lentulus Augur was a contemporary of Augustus and the emperor Tiberius. Born into a senatorial family, he was consul in 14 BC, then proconsul of Asia, a highly lucrative position in keeping with his colossal fortune.

As a result, the Sesterce is a Roman currency of medium value, used for day-to-day transactions, with an exceptional longevity and wide geographical distribution. 
Today, because of their size and history, these coins are highly sought-after by collectors because of the scenes depicted on them (battle scenes, portraits of emperors, etc.), providing evidence of antiquity in the Roman era.

*Chastagnol André. Robert Étienne, Daily life in Pompeii. In: Annales. Economies, sociétés, civilisations. 24th year, N. 2, 1969