We have the following currencies for Rome:
Roman Republic:
Denarius (cca 280 BC-41 BC)
The Imperatorial Republic, path to the Empire (49-27 BC)
Roman Empire:
The Twelve Caesars (27 BC-96 AD)
The Adoptive Emperors and the Antonines (96-192)
The Severans (193-235)
Military Anarchy and Economic Collapse (235-268)
Revival under Illyrian Emperors (268-285)
The Tetrarchy (284-337)
Antoninianus (286-296)
The Constantinian Era (337-363)
The Late Empire and the move to a Byzantine Empire (363-498)
This is a system that combines currencies and rulers/periods. Now that there is a separate field for rulers, we need to separate the currencies and keep strictly currency reforms in this field.
I propose the following currencies:
Roman Republic:
As (~280-221 BC)
1 Decussis = 2 Quincussis = 10 Asses
1 As = 1½ Bes = 2 Semisses = 3 Trientes = 4 Quadrantes = 6 Sextantes = 12 Unciae = 24 Semunciae = 48 Quartunciae
Drachm (? - 235 BC)
Quadrigatus (~ 235 BC - 212 BC)
1 Quadrigatus (~ 235 BC - 212 BC) = 2 Victoriatii (221 BC - 170 BC) ~ 1-1.5 Denarii
Denarius of 10 asses (221 BC-141 BC)
1 Denarius = 2 Quinarii = 3 Tressis = 4 Sestertii = 5 Dupondii = 10 Asses = 12 Dextans = 40/3 Dodrans = 24 Quincunx
1 As = 1½ Bes = 2 Semisses = 3 Trientes = 4 Quadrantes = 6 Sextantes = 12 Unciae = 24 Semunciae = 48 Quartunciae
Denarius of 16 asses (141BC - 27BC)
1 Aureus = 25 Denarii (from 49 BC)
1 Denarius = 2 Quinarii = 4 Sestertii = 8 Dupondii = 16 Asses
1 As = 2 Semisses = 3 Trientes = 4 Quadrantes = 5 Quincunx = 6 Sextantes = 12 Unciae
Roman Empire:
Denarius, Reform of Augustus (27 BC - AD 215)
1 Aureo = 2 Quinario d'oro = 25 Denarii
1 Denarius = 2 Silver Quinarii = 4 Sestertii = 8 Dupondii = 16 Asses
1 As = 2 Semisses = 4 Quadrantes
Antoninianus, Reform of Caracalla (AD 215 - AD 301)
1 Aureo = 25 Denarii
1 Antoninianus = 2 Denarii
1 Denarius = 4 Sestertii = 16 Asses
Argenteus, Reform of Diocletian (AD 293/301 - AD 310/324)
1 Solidus = 10 Argentei
1 Argenteus = 4 Nummi = 20 Radiati = 50 Laureati = 100 Denarii
Solidus, Reform of Constantine (AD 310/324 - AD )
1 Solidus = 2 Semisses = 3 Tremisses = 12 Milarienses = 24 Siliquae = 180 Folles / Centenionales = 7200 Nummi
Of course these are all uncertain educated guesses you can find in literature and we can split the currencies in many ways, so I welcome any opinions, especially from the referees!
Best regards