Although I'm no expert (and that's obvious ), I think the archaeological evidence (which is quite extensive) supports the theory that gold coinage wasn't produced before this period (the Second Punic War 218-202 B.C.). In fact, gold coinage made in Rome stopped after the end of the Second Punic War and didn't resume until the time of Sulla, more than a century later.
Let me plagiarize from Kenneth Harl's book Coinage in the Roman Economy: 300 B.C. to A.D. 700
Gold was not thought necessary for trade and commerce in Ancient Rome, especially after the introduction of silver coinage.
Harl quotes Livy as stating that 269/268 B.C. "was the first time the Roman people began to use silver coins" (p. 26).
By the first year of the Second Punic War, Rome faced a severe shortage of silver, requiring the lowering of the silver content of coins from 97% to 91%. (p. 30) This could have been one of the pressures for the creation of gold coinage.
Romans thought silver was the preferred medium of exchange and the preferred store of value (and not gold).
How many of us today think in terms of platinum or palladium coins, despite their high value?
In many ancient societies, bartering was still an important part of trade. Stored or implied value was to be found in things other than gold coinage. Harl writes, "Etruscan towns, the most sophisticated centers in Italy during the 6th and 5th centuries B.C. never struck gold or silver coins even though they had extensive trade with the Greeks and Carthaginians. Etruscans reserved gold and silver...for plate and jewelry." (p.21) [Harl is probably incorrect in this assertion. Although bronze was the typical Etruscan coinage found, silver and gold coins attributed to the Etruscans have now been found. These silver and gold coins are in the coastal regions, possibly indicative of the exposure to the Greek and Hellenistic influences of gold and silver coinage. The point of this assertion, however, was that Etruscans did not think of silver and gold coinage as essential to their economy.]
According to Harl, Rome preferred silver for their coins and viewed gold as a "regal medal better dedicated to the gods." "The [early] Republic, with no need to hire mercenaries and with limited long distance trade, could afford to dispense with an international gold currency." (p.49)
guy also known as gaius
Addendum: An interesting blog about the philosphy of gold, also quoting Harl's book:
http://seekingalpha.com/article/22732-why-...stand-inflation
What proof that the image is that of a Pig? Nice coin... priceless.