Antoninianus of Gallienus

The antoninianus was the everyday silver-alloy coin of the third-century Roman Empire, and this example belongs to the reign of Gallienus (253-268 AD). It is identified as an antoninianus, rather than a denarius, by the spiked radiate crown worn by the portrait, a convention that marked the coin as a double denomination. The piece shown pairs a radiate male head on the obverse with a standing deity or personification on the reverse.

By Gallienus's reign the antoninianus was no longer good silver but billon, a debased alloy of a little silver in a copper base, often finished with a thin silver wash. As a result these coins are small, light, and today usually show a brown or coppery surface where the original silvering has worn away. The radiate portrait and a divine reverse figure are the defining features of the type.

Gallienus ruled from 253 to 268 AD, first jointly with his father Valerian and, after Valerian's capture by the Persians in 260, as sole emperor. His reign fell in the depths of the third-century crisis, a period of civil war, breakaway regimes, barbarian invasions, and severe financial strain, all of which drove the steady debasement of the coinage.

The antoninianus, introduced earlier in the century under Caracalla, became the workhorse of this inflationary age. Under Gallienus enormous quantities were struck at Rome and at eastern and provincial mints to meet military and state expenses, and the silver content fell sharply over the reign until the coins were essentially bronze with a surface wash. Gallienus is especially known for a broad range of reverse types, including a famous series of gods and animals, produced across multiple mints and workshops (officinae).

Look first at the crown. The defining mark of an antoninianus is the radiate crown, a band of pointed sun-ray spikes around the head, which separates it from the laureate portrait used on the denarius. On this coin the obverse is a radiate male head in profile with a Latin legend around the rim naming Gallienus. The flan is typically small, roughly 18-22 mm, and light, only a few grams, reflecting the debased billon fabric.

The reverse shows a standing deity or personified virtue, identified by its attributes and by the surrounding legend; the exact figure is not fully clear from the image but standing gods and personifications are the norm for the type. The metal reads as billon: expect a coppery or grayish-brown tone, sometimes with patches of surviving silvery wash. Genuine coins are hand-struck, so look for slightly irregular flans, off-center strikes, and crisp but uneven lettering; later issues may carry mint or officina marks in the exergue beneath the reverse figure.

Antoniniani of Gallienus are among the most common of all ancient Roman coins, because they were struck in vast numbers during his reign. For that reason ordinary examples are inexpensive and widely available, and even attractive coins remain accessible compared with Roman gold or good early silver.

Value is driven by the reverse type, the sharpness of the portrait, how much original silvering survives, centering, and overall surface quality. Common reverse types in worn condition sit at the low end, while well-struck coins with strong detail, scarcer reverse types, or substantial surviving silvering command more. Any figure should be treated as a broad guide and checked against recent sales, since condition and reverse type cause a wide spread even within this single emperor's coinage.