Found An Article On The Ancient Roman Monetary System

Quote:
Around 225 BC there was a major monetary reform during which the As was drastically reduced in weight by 50% once again down to 140 grms. At the same time, the As was revalued and now was the equivalent of 6 Asses to the didrachm of silver instead of 3. It was here between the First and Second Punic Wars, that the coinage underwent another drastic and important change. The introduction of a new series of Aes Grave and the replacement of the silver didrachms by the silver quadrigati, which utilized a janiform head of the Dioscuri on the obverse. The Aes Grave became standardized much more so in design than ever before. The types of which were subsequently adopted as the norm for most of the later issues of Republican bronze. The following table shows the obverse types and relative values of the various bronze denominations while the reverse typically portrayed the prow of a galley:

Denomination Design Mark Value - equivalent

As .... Head of Janus:____ "I" = 12 unciae

Semis.. Head of Saturn:___ "S" = 6 unciae

Triens.. Head of Minerva:__ 4 pellets = 4 unciae

Quadrans. Head of Hercules:__ 3 pellets = 3 unciae

Sextans. Head of Mercury:__ 2 pellets = 2 unciae

Uncia... Head of Bellona:___ 1 pellet.