(note: automatic translation; please, allow few days to review it)
The didrachm was coined to Capua in the 312 a.C. with a weight of 6,82 gs. for it allows the commerce with the cities of Greek influence. Initially the coinage in silver was more spread in the south, while that in bronze was diffused to Rome and in the center Italy. Were the themes that appeared on the Roman didrammis also tied up to the Greek world for how much it concerns the registration in Greek characters ΡΩΜΑΙΩΝ (of the Romans).
Subsequently, the didrachm was coined by the 286 a.C. also in Rome with the name of quadrigatus, name done give by Plinio for the presence on the back of Jupiter on a quadriga driven by the Victoria, while on the astute one a juvenile head graduated bifronte is represented. Subsequently on the quadrigatis the registrations will appear "Roman" or "Rome.".
Other silver coin coined beginning from the 221 a.C. it was the vittoriato with a weight of 3,4 gs, whose name derives from the representation on the back of the Victoria that crowns a trophy of weapons. The vittoriato supplanted in the circulation the quadrigato because of the devaluation suffered by this last to succession to the second war punica. The Victorian one, was supplanted in turn by the denarius.
The inheritance of the didramma also continues after the end of the period classical Greek and Roman, thanks to the Arabic coin he/she dictates dirham. The dirham was a silver coin with a weight of 2,79 gs., derived by the play Greek fret through Bisanzio following the conquest of the empire Persiano from the Arabs. How unity of account was introduced in 632, but the first true coin was coined by the caliph omayyade Abd al-Malik (685-705) in its 695/696 monetary reform.
The gold coin, was instead the dinar, with a weight equal to that of the Byzantine solid (4,25 gs.). Multiple some dinar was the estar (19,86 gs.) and the only sottomultiplo was the robai, equal to a quarter of dinar from which it derived then the tarì, term that probably derives from “tarein”, that wants to say “Saracen”.
As coin of copper was had the fulus, derived by the Byzantine follis and Roman.