Roman Republic AR Denarius(18.8 mm, 3.99 g, 12 h), Furius Purpurio, moneyer, circa 169-158 B.C. Rome mint. Helmeted head of Roma right; behind, X. Border of dots / Luna in biga right, holding reins of nearer horse in left hand and reins of further horse and goad in right hand; above, murex-shell; below, PVR; in linear frame, ROMA. Line border. Crawford 187/1; Sydenham 424; BMCRR Italy 420; Babelon Furia 13; Russo RBW 797.
Ex Agora Auctions sale 51 lot 145, ex RBW Collection, ex Crédit Suisse 5, 4/18/86, lot 246
The Latin purpura loosely translates to the English purple, but a more precise description of the specific color family described by this word is "Tyrian purple", a range of purple dyes derived from the excretions of various types of sea snails. Tyrian purple was prized throughout much of the ancient world because unlike other dyes, it did not fade in the sun and in fact, became more intense. Theopompus relates that in Colophon, the prized dye was worth its weight in silver. So what, might you ask, does this have to do with coins? Well, this particular coin bears a murex-shell above the horses on the reverse, along with "PVR", thought to be short for the cognomen Purpureo. The murex shell may simply be a pun on similarity of the cognomen Purpureo to the color purpura, however J.S. Richardson offers another explanation, in his paper "The Triumph, the Praetors and the Senate in the Early Second Century B.C." from The Journal of Roman Studies, Vol. 65 (1975).
According to Richardson, this cognomen first appears in the historical record in reference to the moneyer's ancestor, L. Furius Purpureo, who as praetor in 200 B.C., defeated the last remnants of Hamilcar's invasion force as it traveled through Gaul. Furius had requested assistance from Rome, but the praetor encountered and defeated the enemy forces before the reinforcements sent from Etruria could arrive. After this he traveled to Rome and asked for a triumph, which was quickly granted, making him the first Praetor to receive a triumph, in stark contrast to the usual tradition of only granting triumphs to Consuls. Livy doesn't explicitly say this, but Richardson and others theorize that the cognomen Purpureo refers to the extraordinary achievement of this praetor taking up the "vestis triumphalis" - the Tyrian purple vest worn by individuals during their triumphs.