THE ROSTRAL CROWN.
Agrippa appears on his coins with the rostral crown, a sign of naval victory or command, being made of gold, in resemblance of prows of ships, tied together.
THE MURAL CROWN.
Agrippa is likewise seen with the mural or turretted crown, the prize of first ascending the walls of an enemy’s city.
THE CIVIC CROWN.
The oaken or civic crown is frequent on reverses, as of Galba and others; and was the badge of having saved the life of a citizen, or of many citizens.
THE HELMET.
The helmet appears on coins; as in those of Macedon under the Romans, which have a head of Alexander, sometimes covered with a helmet. Probus also has often the helmet on his coins; and Constantine the first, has helmets of different forms curiously ornamented.
THE NIMBUS OR GLORY.
The nimbus or glory, now peculiar to the saints, was formerly applied to emperors. A nimbus appears round the head of Constantine the second, in a gold coin of that prince; and of Flavia Maxima Fausta, in a gold medallion; and of Justinian in another. But the idea is as ancient as the reign of Augustus, and is found in Roman authors, before it appeared on coins. Oiselius gives a coin of Antoninus Pius, with the nimbus, but this however is doubtful, and may have been some flaw in the coin from which he engraved his representation.