The History of Money Part 3

The Aes, the Denarus, and the Arus (Copper, Silver, and Gold)


February 10, 2015

Roman legends date the founding of the city to around 750 BC. This is earlier than the invention of coins by the Lydians of Anatolia (See History of Money: Part 1). Just like the Greeks, the Romans had an economy based on the trade of bronze (actually bronze and sheep were the early mediums of exchange). In the case of the Romans, the form of the bronze was an ingot called an aes rude (rough bronze). These were irregular in shape and size, and so they needed to be weighed for each transaction.

Around 300 BC, the aes was standardized into an approximately five-pound ingot called the aes signatum (signed bronze). By this time, Greek colonies in Southern Italy were using the Silver Drachma, so the Romans were late to the coinage party.

By about 280 BC, the Romans started minting coins. They had taken over large portions of Italy at this point and had good sources of bronze, but they didn't yet have much access to silver or gold. The bronze coins were called aes grave (Heavy Bronze) and just like the variants of the Greek Drachma, coins were named by their size relative to the aes, and for larger denominations, ingots weighing as much as 50 pounds were cast. These were marked with a Roman numeral to indicate how many aes they represented.

Name Mark Value in Aes
Decussis X 10
Quincussis V 5
Tressis III 3
Dupondius II 2
Aes I 1
Dextans 5/6
Dodrans 3/4
Bes 2/3
Semis 1/2
Quincunx 5/12
Triens 1/3
Quadrans 1/4
Sextans 1/6
Uncia 1/12
Semuncia 1/24
Quartuncia 1/48

In 212 BC, Rome sacked Syracuse and came into possession of substantial stores of Greek silver coinage, which were melted down and used as the basis for the first casting of the new standard currency, the denarius. Because of the greater value of silver, more actual coin value could be carried for less weight. One denarius was a day's wages for a common laborer.

In addition, gold coins were cast for high value, the large bronze and copper ingots being done away with. The gold coins were rare, mostly being a unit of account rather than physical exchange. The late Republican coins and their exchange rates are shown below.

Coin Value in Denarii
Gold Aureus 25
Gold Quinarus 12.5
Silver Denarius 1
Silver Quinarus 1/2
Bronze Sestersus 1/4
Bronze Dupondus 1/8
Copper Aes 1/16
Copper Semiaes 1/32
Copper Quadrantus 1/64

These were the coins of the late Republic and of the Empire until about 300 AD, after which the debasement of the currency required the Emperor Diocletian to stabilize the currency with the Denarius as the smallest coin.

These Roman coins were the unit of exchange from Northern England to Syria until the start of the 5th century. As the Empire was overrun by Germanic Tribes, theses tribes set up Kingdoms, and the Kings minted their own coins.

Next up: How the Anglo Saxon’s copy of the coin systems of the late Empire evolved into the Pound Sterling.