The economic relations of this epoch are clearly mirrored to us even now in the Roman monetary system. Its treatment shows throughout the sagacious merchant. For long gold and silver stood side by side as general means of payment on such a footing that, while for the purpose of general cash-balances a fixed ratio of value was legally laid down between the two metals[39], the giving one metal for the other was not, as a rule, optional, but payment was to be in gold or silver according to the tenor of the bond. In this way the great evils were avoided, that are otherwise inevitably associated with the setting up of two precious metals; the severe gold crises - as about 600, for instance, when in consequence of the discovery of the Tauriscan gold-seams[40] gold as compared with silver fell at once in Italy about 33 1/3 per cent - exercised at least no direct influence on the silver money and retail transactions. The nature of the case implied that, the more transmarine traffic extended, gold the more decidedly rose from the second place to the first; and that it did so, is confirmed by the statements as to the balances in the treasury and as to its transactions; but the government was not thereby induced to introduce gold into the coinage. The coining of gold attempted in the exigency of the Hannibalic war[41] had been long allowed to fall into abeyance; the few gold pieces which Sulla struck as regent were scarcely more than pieces coined for the occasion of his triumphal presents. Silver still as before circulated exclusively as actual money; gold, whether it, as was usual, circulated in bars or bore the stamp of a foreign or possibly even of an inland mint, was taken solely by weight. Nevertheless gold and silver were on a par as means of exchange, and the fraudulent alloying of gold was treated in law, like the issuing of spurious silver money, as a monetary offence. They thus obtained the immense advantage of precluding, in the case of the most important medium of payment, even the possibility of monetary fraud and monetary adulteration. Otherwise the coinage was as copious as it was of exemplary purity. After the silver piece had been reduced in the Hannibalic war from 1/72[42] to 1/84 of a pound[43], it retained for more than three centuries quite the same weight and the same quality; no alloying took place. The copper money became about the beginning of this period quite restricted to small change, and ceased to be employed as formerly in large transactions; for this reason the as was no longer coined after perhaps the beginning of the seventh century, and the copper coinage was confined to the smaller values of a semis (1/4 pence) and under, which could not well be represented in silver.

The sorts of coins were arranged according to a simple principle, and in the then smallest coin of the ordinary issue - the quadrans (1/8 pence) - carried down to the limit of appreciable value. It was a monetary system, which, for the judicious principles on which it was based and for the iron rigour with which they were applied, stands alone in antiquity and has been but rarely paralleled even in modern times.

Yet it had also its weak point. According to a custom, common in all antiquity, but which reached its highest development at Carthage[44], the Roman government issued along with the good silver denarii also denarii of copper plated with silver, which had to be accepted like the former and were just a token-money analogous to our paper currency, with compulsory circulation and recourse on the public chest, inasmuch as it also was not entitled to reject the plated pieces. This was no more an official adulteration of the coinage than our manufacture of paper-money, for they practised the thing quite openly; Marcus Drusus proposed in 663, with the view of gaining the means for his largesses of grain, the sending forth of one plated denarius for every seven silver ones issuing fresh from the mint; nevertheless this measure not only offered a dangerous handle to private forgery, but designedly left the public uncertain whether it was receiving silver or token money, and to what total amount the latter was in circulation. In the embarrassed period of the civil war and of the great financial crisis they seem to have so unduly availed themselves of plating, that a monetary crisis accompanied the financial one, and the quantity of spurious and really worthless pieces rendered dealings extremely insecure. Accordingly during the Cinnan government an enactment was passed by the praetors and tribunes, primarily by Marcus Marius Gratidianus[45], for redeeming all the token-money by silver, and for that purpose an assay-office was established. How far the calling-in was accomplished, tradition has not told us; the coining of token-money itself continued to subsist.

As to the provinces, in accordance with the setting aside of gold money on principle, the coining of gold was nowhere permitted, not even in the client-states; so that a gold coinage at this period occurs only where Rome had nothing at all to say, especially among the Celts to the north of the Cevennes and among the states in revolt against Rome; the Italians, for instance, as well as Mithradates Eupator struck gold coins. The government seems to have made efforts to bring the coinage of silver also more and more into its hands, particularly in the west. In Africa and Sardinia the Carthaginian gold and silver money may have remained in circulation even after the fall of the Carthaginian state; but no coinage of precious metals took place there after either the Carthaginian or the Roman standard, and certainly very soon after the Romans took possession, the denarius introduced from Italy acquired the predominance in the transactions of the two countries.

In Spain and Sicily, which came earlier to the Romans and experienced altogether a milder treatment, silver was no doubt coined under the Roman rule, and indeed in the former country the silver coinage was first called into existence by the Romans and based on the Roman standard[46]; but there exist good grounds for the supposition, that even in these two countries, at least from the beginning of the seventh century, the provincial and urban mints were obliged to restrict their issues to copper small money.

Only in Narbonese Gaul the right of coining silver could not be withdrawn from the old-allied and considerable free city of Massilia; and the same was presumably true of the Greek cities in Illyria, Apollonia and Dyrrhachium. But the privilege of these communities to coin money was restricted indirectly by the fact, that the three-quarter denarius, which by ordinance of the Roman government was coined both at Massilia and in Illyria, and which had been under the name of victoriatus received into the Roman monetary system[47], was about the middle of the seventh century set aside in the latter; the effect of which necessarily was, that the Massiliot and Illyrian currency was driven out of Upper Italy and only remained in circulation, over and above its native field, perhaps in the regions of the Alps and the Danube. Such progress had thus been made already in this epoch, that the standard of the denarius exclusively prevailed in the whole western division of the Roman state; for Italy, Sicily - of which it is as respects the beginning of the next period expressly attested, that no other silver money circulated there but the denarius - Sardinia, Africa, used exclusively Roman silver money, and the provincial silver still current in Spain as well as the silver money of the Massiliots and Illyrians were at least struck after the standard of the denarius.