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The Roman didrachm comes from the analogous coin of the monetary system in ancient Greece, based on the drachma. The name drachma (dracmh) is derived from the verb "to grab" (drassomai) and it supports the hypothesis that the economic value of this coin had to come from one "handful" (drax) of other objects, presumably oboloi.
Obelos, in turn, comes from obelos which means "iron spit" and it recalls to the usage of the metal in shape of rods in the commercial exchanges since the VIII to the V century B.C., before the adoption of the coin. In the Greek coinage, the drachma in silver had a value equal to 6 oboloi.
Actually, the drachma doesn't represent an absolute values but it is the half of a stater (stathr), which is the real reference value. In fact, the term stater refers to the two dishes of the balance in equilibrium; also today the "steelyard" it is a type of weighing scale. The stater, therefore, represents the general value of two drammes.
The stater represented the monetary unity for the gold coins, with a weight of around 8,7 g. For the coins of smaller value, instead, the silver was employed, with a relationship in value of 1:10 with the parity gold of weight; how base of the silver coins is used the drachma.
As a consequence of these relationships of weight, the parity of weight among the based system on the stater and that based on the play, therefore, it is had among stater and didrachm, that it is note the multiple of the drachma that has the double one of it of the weight.
But the Greek coin of big long more used, from the V century a.C. thin to Alexander Magno, it was the tetradramma with a value of four drachmas. On the right the head was represented in profile of Atena and on the reverse an owl, the sacred animal to the goddess. Other multiples of the play were the mine (in Greek mna: mna), equal to 100 drammes and the talent (talanton), equal to 60 mines, talent that represents the maximum unity ponder her in the oriental and Greek world.
Concerning the coins of lower value, these were realized in copper, with a monetary unity given by the litra (litra), become then the unity of weight for the Romans of the it hovers, term that also points out the bilancia.
The adoption in the Greek colonies in Sicily of the copper to weight for the commercial exchanges, forced to fix a relationship among the coin in silver of the Greek cities and the unity of value of the local populations. Was you/he/she created, therefore, does one hover in silver with a value of 1/5 of play, with which it replaced subsequently him one it hovers in bronze.
Other fraction of the offering it was the chalkus (from the Greek? to????, copper), that was a coin in copper of the Attica, with a value equal to the eighth part of the obolo.
A common characteristic of the Greek coins it is that to be characterized by a notable relief of the images in them represent. The images were related to divinity or to animals or produced typical of the places in which were coined and therefore, gives the notable extension of the influence of ancient Greece and the elevated number of mints, an elevated number of different monetary denominations.
The contacts in Rome with Great Greece, gotten used for a long time by now to the use of the coin, they brought the Romans to adopt coins that, although is issued under the authority in Rome, as they testify the adopted legendes, you/they were coined in mints of Campania, according to the system ponder her Greek.
The beginning of these series is individualized in two following issues of a litra in bronze that introduces to the astute one the head of Apollo and to the reverse a bull with human face; the legenda of the first one points out Rome in Greek characters, the second in Latin characters (ROMAION).
Subsequently, beginning from the end of the IV century or from the first decades of the III a.C. three silver series were coined, with Roman legenda whose value equivaleva to that of the didramma (g.7,40) and of the Greek drachma (g.3,30).
The following series, perhaps issued to Rome, they bring the legenda Rome and you/they have hung meeting places. Last issue is that pointed out by Plinio as quadrigato, so called for the presence on the reverse of Jupiter on a quadriga driven by the Victoria, while to the astute one introduces a juvenile head graduated bifronte.
To this last issue a gold coin was placed side by side with the same juvenile head bifronte to the astute one and a scene of oath (two warriors that swear on a piglet held by a third warrior) to the reverse.
Both the coins seem to refer to the victory brought by the Romans on the Sannitis and their coalition near Sentinum in the 295 a.C. and to the consequent peace of the 290 a.C. celebrated, note, with the oath of fidelity.