In the Roman currency system, the denarius (plural: denarii) was a small silver coin first minted in 211 BC. It was the most common coin produced for circulation but was slowly debased until its replacement by the antoninianus. History The denarius was first struck in or about 211 BC during the Roman Republic and at the same time as the Second Punic War, with a weight of 4.5 grams on average at the time or 1/72 of a Roman Pound. It remained at this weight for a while and then decreased to about… (More on Denarius)