(note: automatic translation; please, allow few days to review it)
Before Giulio Cesare, Rome sent forth coins in gold in non continuous way. A first issue, called gold of the oath, it was had around the 220 a.C. tracing the characteristics of the quadrigatis of Greek formulation; the weight was of 6 scruples, correspondent to 6,82 gs.. The name derives from the scene of two warriors that you/they swear on a piglet held by a third warrior to the back, that seems to remember the victory brought by the Romans on the Sannitis and their coalition near Sentinum in the 295 a.C. and to the oath of fidelity followed to the peace of the 290 a.C..
A second series in gold, suitable as "marte/aquila", you/he/she was coined in the 209 a.C. with a weight of 3, 2 and 1 scruple. Third series was that issued in the 197 a.C. in Greece favor of the consul Tito Quinzio Flaminio, consistent in a statere from the weight of around 8g..
The first golden of Roman formulation (denarius aureus) it was had to the time of the war of Silla against Mitridate (88-85 a.Cs.), with a weight equal to 1/30 of the Roman pound (10,8 gs) and origin of the metal presumably from the loots of war.
As fractions of the aureus there was the quinario (equal to half golden) and the relationship between gold and silver was of a golden against 25 moneys. How multiple was had the quaternione, correspondent to 4 aurei.
In the 61 a.C., during the government of Pompeo, the weight of the golden one was brought then to 1/36 of the it hovers (around 9 g).
The issue in Rome with continuity of coins in gold, however, begins only after the conquest of Caesar of the Gallia and the availability of precious metal coming from its mines. In the 48 a.C., under Caesar, the weight of the golden one was fixed at first to 1/38 (8,55g) and then to 1/40 of it hovers (8,02g). This value maintained him stable for the whole period of the civil wars, up to the principality of august.
The mass of the golden one decreased to 1/45 of pound with the monetary reform of Nerone and with the reform of Caracalla the weight it subsequently came meeting place to 1/50 of pound.
The end of the golden one was had in 309 with the introduction of the solid from Costantino I. While the solid was of greater and thinner diameter, the golden one was of dimensions similar to the denarius, with which it often shared the same types.