Caligula Dupondius, RIC I (second edition) Gaius/Caligula 34

Monetary Context and Denominational System

The dupondius occupied an established structural role within the trimetallic monetary framework instituted under Augustus around 23 BC. Valued at two asses, half a sestertius, or an eighth of a silver denarius, the dupondius served everyday medium-value market transactions across Italy and the western provinces. Under the Augustan reform, the denomination was deliberately differentiated from the copper as by its metal composition: dupondii were struck in orichalcum, a golden-toned brass alloy of copper and zinc, whereas asses were struck in relatively pure red copper. This alloy differentiation allowed the state to tariff the orichalcum dupondius at twice the value of an as despite having a closely comparable physical size and mass. Upon succeeding Tiberius in March of AD 37, Caligula inherited an imperial treasury that had amassed significant reserves but had maintained a conservative base-metal minting policy in Rome during Tiberius's final years. Caligula immediately used the metropolitan brass and bronze coinage to execute a rapid ideological reset. The issue of RIC I (second edition) Gaius/Caligula 34 occurred within this inaugural surge of bronze output. While the reigning princeps himself appeared on the monumental sestertii and certain copper asses, the dupondius was reserved specifically for posthumous commemoration of his family, cementing the currency's combined function as legal tender and public imperial communication.

Production, Alloy, and Mint Attribution

RIC 34 was produced exclusively by the imperial mint at Rome. Modern numismatic consensus, based on stylistic uniformity, die studies, and metallurgical analysis, assigns the entire initial run of Caligula's official base-metal coinage to the capital's centralized workshops. The coin was manufactured from orichalcum, which during the early Julio-Claudian period typically contained between 15 and 22 percent zinc, imparting a bright golden appearance when newly minted. This golden hue prevented market confusion with copper asses of similar diameter. Flans were cast in open or two-part moulds before being struck between engraved iron dies. The theoretical weight standard for the dupondius under Gaius remained aligned with the Augustan benchmark of roughly 12.5 to 13.0 grams, though recorded specimens exhibit normal manufacturing variances ranging approximately from 11.0 to 14.5 grams. Diameters typically span between 28 and 30 millimetres. The coin dies were aligned predominantly at six o'clock or twelve o'clock, reflecting the regularized mechanical practices of the Roman mint. Surviving examples demonstrate careful die engraving characterized by high-relief equestrian figures and deeply cut, classical lettering.

Obverse Typology and Iconography

The obverse design departs from the conventional imperial portraiture of early Julio-Claudian dupondii, which frequently showed the princeps or an individual deified predecessor wearing a radiate crown. Instead, RIC 34 presents an equestrian scene featuring Nero Caesar and Drusus Caesar riding side by side toward the right. The two youths are depicted as youthful Roman equites, their right arms raised or controlling reins, clad in tunics with cloaks flying outward behind them to convey dynamic forward movement. Their horses gallop or trot in close parallel formation. This iconography alludes directly to the transvectio equitum, the annual ceremonial parade of Roman cavalrymen revived under Augustus, while honouring the princely status of Germanicus's two eldest sons who had once been hailed as heirs to the empire before being targeted and condemned under Tiberius and Sejanus. By commemorating Nero (starved to death on Pontia in AD 31) and Drusus (starved in the lower Palatine dungeons in AD 33), Caligula publicly restored their collective dignity and aligned his regime with the memory of his tragic, popular brothers. The composition is compact and energetic, adapted specifically to the circular field of the dupondius flan.

Reverse Typology and Senatorial Inscription

In sharp contrast to the dynamic pictorial obverse, the reverse of RIC 34 is epigraphic and structural. The central field is dominated by the monumental letters 'S C', standing for 'Senatus Consulto' ('by decree of the Senate'). This traditional formula was standard on metropolitan Roman base-metal coinage from the reign of Augustus onward, denoting the formal constitutional sanction of the Senate in approving the issue of bronze and brass currency while the princeps held ultimate monetary authority. Surrounding the central letters is a continuous circular legend containing the imperial titles of Caligula. The design lacks any auxiliary pictorial elements, such as wreaths, altars, or divine personifications, placing complete visual emphasis on the emperor's official authority and the senatorial mandate. The lettering is neatly laid out in a single uninterrupted circle conforming to the flan's outer border, punctuated by uniform raised dots. This minimalist design emphasizes institutional legitimacy alongside the personal filial and fraternal piety declared on the obverse.

Inscriptions, Epigraphy, and Titulature

The inscriptions on RIC 34 provide clear epigraphic dating and ideological framing. The obverse carries the legend 'NERO ET DRVSVS CAESARES', read outward along the lower and lateral borders or arched across the top, identifying the riders as Nero Caesar and Drusus Caesar. The absence of additional divine epithets reflects that neither brother was consecrated as a divus; they were honoured as deceased imperial princes and heroic members of the domus Augusta rather than worshipped as gods. The reverse inscription reads 'C CAESAR AVG GERMANICVS PON M TR POT', expanding to 'Caius Caesar Augustus Germanicus, Pontifex Maximus, Tribunicia Potestate'. This titles Caligula with his official imperial praenomen and cognomen, his inheritance of the prestigious title Germanicus from his father, his post as chief priest (Pontifex Maximus), and his assumption of tribunician power (Tribunicia Potestas). Significantly, this initial variety lacks any numerical iteration following 'TR POT', firmly confining the striking period to his first tribunician year between his accession in March AD 37 and the renewal of his tribunician power in early AD 38. The epigraphy is characterized by clean Augustan capitals with square proportions and consistent letter spacing.

Typological Classification and Chronological Placement

In the standard reference corpus 'The Roman Imperial Coinage' (revised second edition of Volume I, edited by C. H. V. Sutherland in 1984), this specific issue is designated as Caligula number 34. It forms part of an interconnected sequence of commemorative issues produced in Rome at the beginning of the reign. Parallel issues struck in the same opening emission included the celebrated sestertii honouring Caligula's mother Agrippina the Elder (RIC 55) and his deceased father Germanicus (RIC 35, 57). Chronologically, RIC 34 is distinguished from later dupondius varieties that carry updated tribunician iterations, such as 'TR POT III' or 'TR POT IIII', struck in subsequent regnal years between AD 39 and 41 (e.g., RIC 42 and RIC 49). Because the legend on RIC 34 records unnumbered 'TR POT', its striking commenced after Caligula received the tribunicia potestas in mid-March AD 37 and concluded before its second reckoning, making it an exact diagnostic marker for the first twelve months of his reign. Minor die-cutting variations exist in horse poses and letter breaks, but the design and textual formula remain strictly consistent across the issue.

Circulation, Hoard Evidence, and Survival

Dupondii of Caligula entered wide circulation across the Roman Empire, although their distribution was most heavily concentrated in Italy, Gaul, the Rhine frontier, and the Iberian Peninsula. Archaeological finds from military camps and civic settlements throughout the western provinces demonstrate that Caligula's base-metal coinage circulated alongside earlier Augustan and Tiberian bronzes for several decades. Because Caligula ruled for less than four years, his total bronze volume was smaller than the massive outputs of Augustus or Claudius, but hoard evidence proves that his coins were not subjected to systematic official demonetization or universal melting down after his assassination in AD 41. While Caligula's own portrait issues were occasionally targeted for defacement or countermarking under Claudius, the Nero and Drusus dupondii honouring Germanicus's popular sons generally escaped such hostility and continued circulating as ordinary fractional currency. Over decades of continued use, specimens of RIC 34 accumulated substantial wear, frequently remaining in local coin pools well into the Flavian period. Consequently, high-grade specimens retaining crisp detail on the horses' manes and riders' drapery are rare, whereas well-circulated examples with smoothed high points are standard across archaeological assemblages.

References

1. Coins of the Roman Empire in the British Museum, Volume I: Augustus to Vitellius. pp. 154-156, nos. 44-48
2. Catalogue des monnaies de l'Empire romain, II: De Tibere a Neron. pp. 88-89
3. Roman Coins from the Earliest Times to the Fall of the Western Empire. pp. 110-115
4. Online Coins of the Roman Empire: RIC I (second edition) Gaius/Caligula 34. ric.1(2).gai.34
5. The Roman Imperial Coinage, Volume I: From 31 BC to AD 69 (Revised Edition). p. 111, no. 34