The dime-sized coin is famous for the image of its issuer, one of the assassins, Marcus Junius Brutus, on the obverse.
The coin is ranked No. 1 in a survey of experts for the book 100 Greatest Ancient Coins by Harlan J. Berk.
Brutus was one of two chief co-conspirators leading a cabal of Roman senators that surrounded and stabbed Caesar during a Senate proceeding. The conspirators, fearful of a tyranny ushered in by Caesar, expected to be hailed as liberators, but the Roman populace was horrified by Caesar’s murder and wanted the assassins punished. Brutus fled and soon waged war against Caesar’s successors.
After being proclaimed imperator, Brutus began issuing coins to pay his army. The Eid Mar coins of mid-42 B.C., with the pileus or cap of liberty between the daggers that executed Caesar, is Brutus’ final coinage type. The design is notable for the irony of its use of a portrait of Brutus.
“Caesar, a mere two years earlier, had been the first Roman to place his own portrait on Roman coins, and that was just the sort of monarchial innovation for which he had been assassinated,” Berk wrote.
Eid Mar denarii were deliberately recalled and melted down by the victors of the second battle of Philippi on Oct. 23, 42 B.C., Mark Antony and Octavian.
Today these coins regularly trade for hundreds of thousands of dollars. An estimated population of some 80 examples was known in 2008 when Berk’s book was published, “but many more than 80 people want one of these coins and can afford the $100,000-plus price tag.”
The size, weight and silver purity of the denarius declined from the reign of Nero (54 to 68 A.D.) until its content was about 50 percent circa 193 to 211 during the reign of Septimius Severus.
The antoninianus was introduced in 215 to spark more interest in the silver coinage of Rome, but it didn’t work, and the last true denarii were struck in the 240s, “and attempts to reestablish the coin later in the third century met with no success,” according to Richard Doty in The MacMillan Encyclopedic Dictionary of Numismatics.
The name, however, survived, inspiring the medieval coinage known as the denier, denar, denaro and so on, including the medieval silver penny of Britain.
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