"Though the Roman Empire occupied Jerusalem and certainly spread its currency there, the only known Roman coins from the ancient Jewish capital have all come to historians and archaeologists through collectors, with uncertain provenance. An exception is a gold coin recently discovered near excavations of wealthy first century priestly houses on Jerusalem's Mt. Zion. Dated to 56 CE, it may be an remnant of looting at the time of the city's destruction in 70 CE." Source: Science Daily.
"... The gold coin (aureus) bears the bare-headed portrait of the young Nero as Caesar. The lettering around the edge of the coin reads: NERO CAESAR AVG IMP. On the reverse of the coin is a depiction of an oak wreath containing the letters 'EX S C,' with the surrounding inscription 'PONTIF MAX TR P III.' Importantly, these inscriptions help to work out the date when the coin was struck as 56/57 AD."
Note: Nero was emperor from 54-68, so this coin dates back to the early years of his reign when the aureus was probably worth a lot more than it was in later years. "In AD 64 Nero reduced the weight of the aureus and the weight and fineness of the denarius ..," according to the Oxford Classical Dictionary (3rd ed. revised). This debasement of the coinage was a symptom of the financial problems that contributed to the decline and eventual collapse of the western Roman empire.
According to Science Daily, "[This particular coin] dates to a little more than a decade before the destruction of Jerusalem by the Romans in 70 AD, and was found in rubble material outside the ruins of the 1st Century Jewish villas the team has been excavating. The team has hypothesized that the large houses may have belonged to wealthy members of the priestly caste, and it may have come from one of their stores of wealth."
Why would Jewish priests have been rich? It's an interesting question. Did they draw large salaries or was something else going on? As it turns out, the temple was more than just a simple house of worship. It was also a bank and commercial market than ran its own treasury and foreign exchange:
"In the period of the Second Temple vast numbers of Jews streamed to Palestine and Jerusalem 'out or every nation under heaven' (Acts 2:5), taking with them considerable sums of money in foreign currencies," according to the Jewish Virtual Library. "This is referred to in the famous instance of Jesus' driving the money changers out of the Temple (Matt. 21:12). Not only did these foreign coins have to be changed but also ordinary deposits were often handed over to the Temple authorities for safe deposit in the Temple treasury (Jos., Wars 6:281–2). Thus Jerusalem became a sort of central bourse and exchange mart, and the Temple vaults served as 'safe deposits' in which every type of coin was represented ..." Next video shows a virtual reconstruction of the Second Temple:
Temple authorities charged transaction fees for converting currencies from one denomination or another. "This premium seems to have varied from 4 percent to 8 percent," according to the Jewish Virtual Library. They were also bankers who paid out interest on deposits and presumably made a good living through investments, and I wouldn't be surprised if they indulged in a little skimming on the side. The temple was a major financial and religious institution, kind of like a combination of a mega-church and Bank of America.
It would be interesting to know the actual history of this auerus recently discovered in Jerusalem. How did it end up in the villa of wealthy priest, for instance, and why wasn't it moved to a safe location before the Roman invasion? If it was looted from one of the temple's "safe deposits," who did the looting? The Romans? If so, did the rest of the treasure end up back in Rome with the other spoils from the temple, or were a group of legionaries carrying out an act of private enterprise? We'll probably never know, but there's a lot of history hidden behind this single gold coin.