Half Centenionalis of Constans or Constantius II

The half centenionalis is a small Roman base-metal coin of the mid-fourth century AD, here attributed to one of two brothers who ruled after Constantine the Great: Constans (Augustus AD 337-350) or Constantius II (Augustus AD 337-361). The two are grouped together because worn examples of this size share almost identical fabric, portrait style, and reverse types, and a heavily circulated coin often cannot be pinned to one emperor with certainty.

The obverse observed on this coin carries a diademed imperial portrait facing right, now worn, surrounded by a Latin legend that named the ruler and his titles. The reverse, also worn, would originally have shown a standard mid-century type such as paired Victories, soldiers and standards, or a vota inscription within a wreath. In hand it is a small, thin bronze disc, coppery brown where any surface enrichment has worn away.

"Half centenionalis" is a modern convenience label rather than an ancient name. The late Roman bronze denominations are known mainly from a few laws and are debated by numismatists, who commonly describe coins of this size by module (for example AE3 or AE4) when the exact denomination is uncertain.

Constans and Constantius II were sons of Constantine I who, together with their brother Constantine II, divided the empire after their father's death in AD 337. Constans took the central and western provinces, while Constantius II governed the East. Constans was overthrown and killed by the usurper Magnentius in AD 350; Constantius II eventually defeated Magnentius and ruled as sole Augustus until his death in AD 361. Their coinage runs through the middle decades of the fourth century.

This was a period of repeated adjustment to the bronze coinage. Constantine and his successors issued a series of small billon and bronze denominations whose weights and sizes were reduced and reformed several times. A major reform associated with Constans and Constantius II around AD 348 introduced the FEL TEMP REPARATIO ("restoration of happy times") coinage, along with a set of denomination names, including the centenionalis, that appear in imperial legislation but are difficult to match precisely to surviving coins.

Because of this uncertainty, modern catalogues often use terms such as centenionalis and half centenionalis, or simply the size classes AE2, AE3, and AE4, to describe the different modules. A small coin of this era attributed to Constans or Constantius II sits within that reformed bronze system, struck at imperial mints across the empire in very large numbers.

Start with the portrait and the fabric. This is a small, thin bronze coin bearing a right-facing imperial bust, typically diademed (wearing a pearl or rosette diadem) and draped and cuirassed, in the style of Constantine's dynasty. The surrounding obverse legend would have named the emperor, most often in forms such as DN CONSTANS PF AVG or DN CONSTANTIVS PF AVG; where the legend survives, the name CONSTANS or CONSTANTIVS is the key to attribution. On a worn coin like this one the legend may be illegible, which is why it is catalogued to either brother.

The reverse carries one of the standard mid-century types. Common choices for this size include two Victories facing each other and holding wreaths (VICTORIAE DD AVGG Q NN), two soldiers flanking one or two standards (GLORIA EXERCITVS), or a vow inscription such as VOT XX MVLT XXX set within a wreath. Matching the worn design to one of these standard types, together with any surviving reverse legend, is how the coin is identified.

By size and metal it is a small bronze, commonly around 14-18 mm and roughly 1.5-2.5 grams, struck in copper alloy that sometimes carried a slight silvering now generally lost. Look in the reverse exergue for a mint mark, a short string of letters that identifies the mint and workshop and can place the coin to a specific city such as Rome, Aquileia, Siscia, Thessalonica, Constantinople, Antioch, or Alexandria.

Small bronzes of Constans and Constantius II are among the most abundant of all late Roman coins, produced in enormous quantities across many mints, so they are inexpensive and widely available. A worn example such as this one, with an unclear portrait and reverse, generally trades in the low single-digit to low tens of dollars, in line with ordinary uncleaned or lightly circulated late Roman bronze.

Value rises with legibility and eye appeal. Coins with a sharp portrait, a fully readable obverse legend that fixes the emperor, a clear reverse type, and a complete mint mark are worth more than a worn piece that can only be attributed to "Constans or Constantius II." Scarcer reverse types, less common mints, and any surviving silvering add to desirability.

These figures are general context rather than an appraisal. Condition, the specific type and mint, and whether the coin can be firmly attributed to one emperor all affect price, and an individual coin can fall outside these ranges.