Antoninus Pius Sestertius, RIC III Antoninus Pius 624a

Monetary Context

Under Antoninus Pius, the imperial monetary system continued the stable bimetallic and base-metal structure established during the Augustan reforms and consolidated under the Flavians and Trajan. The brass or bronze sestertius remained the principal fractional workhorse of public expenditure, civic building, and domestic transactions throughout the Western provinces and Italy. As the largest regular base-metal denomination, valued at four asses or one quarter of a silver denarius, the sestertius offered an exceptionally broad flan that served as an ideological canvas for imperial propaganda. In the early 140s AD, Antoninus Pius directed significant mint resources toward celebrating traditional Roman religion, archaic ancestral virtues, and foundation mythology, anticipating the monumental celebration of Rome's nine-hundredth anniversary in AD 148.

Production and Mints

The issue RIC III Antoninus Pius 624a was produced exclusively by the imperial mint in Rome, which held a near-monopoly on regular senatorial bronze striking in the West. Sestertii of this period were struck from orichalcum, a copper-zinc brass alloy prized for its bright, golden color when newly minted, although metallurgical compositions varied over the second century as recycling of older brass altered zinc contents. Surviving specimens across the broader sestertius series of Pius demonstrate a standard target weight around 25 to 27 grams and flan diameters typically spanning 31 to 34 millimeters, though individual planchet weights fluctuated widely in regular production due to bulk al marco manufacturing techniques.

Obverse Design

The obverse displays a mature, dignified portrait of Antoninus Pius facing right. He is shown bare-necked with a laurel wreath tied at the nape of his neck, rendered in the classicizing, serene style that characterizes middle-period Antonine portraiture. Die cutters executed the portrait with careful attention to the emperor's curled hair, short beard, and composed facial features, avoiding the aggressive military demeanor of Trajan while retaining imperial gravitas.

Reverse Iconography

The reverse iconography portrays Romulus in dynamic motion, advancing towards the right. He is depicted bare-headed and dressed in full Roman military costume, comprising a tunic, cuirass, and boots. In his right hand, Romulus carries a spear horizontally, while his left hand supports a military trophy rested across his left shoulder. Flanking the lower fields is the standard formula S C, indicating production under senatorial authority. The imagery evokes Romulus as Quirinus and victor, celebrating the warlike founder whose martial success laid the foundation for the enduring pax under Antoninus Pius.

Inscriptions and Epigraphy

The obverse legend reads ANTONINVS AVG PIVS P P TR P COS III, providing the titular basis for dating the issue. It details Antoninus's formal imperial style, including his cognomen Pius, his titles as Pater Patriae and holder of tribunician power, and his third consulship, entered on January 1, AD 140. The reverse legend ROMVLO AVGVSTO, meaning 'To Romulus Augustus' or 'To the August Romulus,' represents a profound epigraphic statement linking Romulus directly to the honorific Augustus. The dative form marks a dedication to the deified founder, celebrating him simultaneously as an ancestral protector and as a mythological prototype of the reigning emperor.

Typology and Chronology

Harold Mattingly and Edward A. Sydenham catalogued this specific variety as RIC III 624a within the third consulship coinage of Antoninus Pius, dating the production between AD 140 and AD 144 before the emperor assumed his fourth consulship in AD 145. Type 624a is defined by the laureate head right without additional drapery. It stands alongside closely related sub-types, such as RIC 624b, which feature drapery or altered bust orientations. The Romulo Augusto theme also appeared concurrently on middle bronze denominations, forming a coordinated multi-denominational release that highlighted the archaic heritage of Rome.

Circulation and Survival

Sestertii of the Antonine era circulated widely across the Roman Empire, seeing intensive use in commercial centers, military garrisons along the Rhine and Danube frontiers, and domestic Italian markets. Due to their substantial intrinsic value relative to minor copper quadrantes and asses, sestertii frequently remained in active circulation for several decades, often until the monetary debasements of the mid-third century AD. As a result, extant specimens of RIC III 624a often exhibit substantial surface wear, smoothing, and ancient patination, with fully unworn examples remaining comparatively scarce.

References

1. Coins of the Roman Empire in the British Museum, Vol. IV: Antoninus Pius to Commodus. pp. 195-196
2. Online Coins of the Roman Empire: RIC III Antoninus Pius 624a. ric.3.ant.624a
3. The Roman Imperial Coinage, Vol. III: Antoninus Pius to Commodus. p. 110, no. 624a
4. Untersuchungen zur romischen Reichspragung des zweiten Jahrhunderts, Teil II: Die Reichspragung zur Zeit des Antoninus Pius. Type 819