MONETA. - A piece of metal of a determined weight, generally round in shape and bearing on its two faces or, more rarely, on only one, a device and a legend, or only one of these. The obverse of the coin is the face that presents the principal type, or the one most interesting from a historical, archaeological or artistic point of view; the reverse is the face that shows elements of secondary importance with respect to the principal type.
The invention of the coin cannot be placed exactly in time or space, but should rather be considered as the result of the slow evolution of the metallic medium of exchange, an evolution caused by the extension and growing complexity of commercial relations, and which finds its final stage of development in the innovation by which the State monopolizes the issuance of the coin, at the same time fixing and guaranteeing its type, metallic alloy and weight. In the West this last and definitive phase of development is accomplished in the 7th century B.C., in the Hellenic world. In the middle of the 4th century, Rome too begins the issuance of its own coin.
Even in antiquity, as in modern times, the metals coined were, with exceptions, gold, silver and bronze. Gold was the base metal of the monetary system of the Eastern world (Lydia, Persia) at first, then of the great Hellenistic monarchies (Macedonia, Syria, Egypt) and finally of the Roman Empire and the Byzantine Empire. It was always struck almost pure, both among the Greeks and among the Romans, down to the Byzantine Empire. Silver, on the other hand, was the basis of coinage among the Greeks, for whom it constituted for several centuries the only coined metal, and among the Romans of the Republic, who struck it in great abundance together with bronze. The latter was the true coin of the Italic peoples and played a very great part also in the coinage of Rome, of which it constituted, before the striking of silver, the only coin, and where it always represented a preponderant part of circulation, even in the imperial age.
The systems of manufacturing coins adopted in antiquity were two: striking and casting; with the first, more frequently used, the blank disc of smooth metal was struck between two dies, bearing in intaglio the type that was to be impressed on one or both faces; with the second, the molten metal was poured into a mold with the intaglio of the piece to be coined, so that at the same time one obtained both the blank disc and the impression on the two faces. Naturally the process of manufacturing the dies was much more complex than it is today, and the technical skill and artistic abilities of the engraver had greater value. A phenomenon that is frequently encountered in antiquity, and not unusual even in the modern era, is the official debasement of the alloy of the coin. This occurred only for silver, gold having always preserved its purity. Together with the debasement of the alloy there is another form of monetary fraud, that of plated coins, that is, coins composed of a core of base metal, generally copper, covered with a thin film of silver. This system was adopted various times in antiquity, and the surviving coins and the literary sources preserve the memory of it.
Bibliography2 works
Franco Panvini Rosati