After the death of Trajan Decius and his son Herennius Etruscus in 251 CE, his younger son Hostilian ruled jointly with Trebonianus Gallus, who was acclaimed Emperor by the troops. Hostilian died shortly thereafter, and Gallus’ son Volusian became the second Augustus. The shared power is reflected on this coin, minted in Rome, by the additional G at the end of AVG, which indicates that the legend, were it not abbreviated, would read PIETAS AVGVSTORVM (“piety of the [plural] Augusti”) rather than PIETAS AVGVSTI (“piety of Augustus”). Piety was always a popular theme among the emperors, but the plague raging through Rome may have been an additional reason for her appearance on coin types during this time period (between 251 and 253). The antoninianus was a denomination of coin introduced by Caracalla. It was worth two denarii, but only contained about 1.6 the amount of silver in it, which no doubt proved beneficial to the imperial treasury. An antoninianus can be distinguished from a denarius by the fact that obverse portraits of the emperors on these coins wear radiate crowns. Reina Callier 2011.