Some of the most common ancient Roman coins include the aureus (gold), denarius (silver), and the sestertius (bronze). These coins were minted from half way through the third century BC till half way through the third century AD.
Antoninianus – This coin, valued at 2 denarii, was brought into play in the Roman Empire by Caracalla in 215. Initially launched as a silver coin, it was later lowered down to the bronze metallic appearance. The silver coin looked analogous to the denarius. The difference was it was larger and its characteristic trait was that it featured the emperor wearing a crown and hence was valued almost twice that of a denarius.
This coin was highly responsible for increasing inflation as it was a fact that the actual silver usage was just 1.5 denarii. As the many emperors and rebels paid their soldiers with them, the antoninianus lost even more silver content with every new issue until nearly the entire coin was made of bronze. Shop owners to compensate for this lower silver content slowly raised their prices.
Denarius – The most widely used coin in the Roman Empire and it was made up of silver, minted initially in 211 BC. For the first century its weight remained around 4 grams but later got degraded to 3.4 under the reign of Nero. Till the middle of the third century the predominance of this coin prevailed but after the launch of the antoninianus this coin was discontinued. It was also observed that the last insurance of these coins were in the bronze metal shape and were found in 270 to 275 AD.
Initially with the weight of 4 grams it was supposed to net ten times the asses and hence it was named as “denaris.” Even after their discontinuation, the legacy of these coins continued and was used by Arabs in particular.
Sestertius – This coin was initially a small silver coin priced at one quarter of denarius. However in 23 BC during the reformation of Augustus the coin equaled to the domination of a huge brass coin. Initially they were manufactured at the mint of Rome but when Nero came to power, these coins were produced at the mint of Lyon. These brass coins weighed around 28 grams and had a diameter of 34 mm and were almost 4mm in thickness.
There was a notable difference between brass and bronze for the Romans. Brass was considered as double the value of bronze as the former one resembled gold like appearance and was termed as “gold copper.” The last sestertius coins were considered to be minted during the Aurelian.