The Quinarius denomination
The quinarius was a small silver Roman coin valued at half a denarius.

Initially, the quinarius was struck for a few years, along with the silver sestertius, following the introduction of the denarius in 211 BC. At this time the quinarius was valued at 5 asses.

The coin was reintroduced in 101 BC as a replacement for the victoriatus, this time valued at 8 asses due to retariffing of the denarius to 16 asses in 118 BC.

For a few years following its reintroduction, large quantities of quinarii were produced, mostly for circulation in Gaul. The coin was produced sporadically until the 3rd century. It was also occasionally struck in gold.
Quinarius
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An AR Quinarius struck 25-23 BC in Emerita
Obverse: AVGVST, Bare head of Augustus facing left

Reverse: P CARISI LEG, Victory standing facing right, crowning trophy of captured arms, dagger and curved sword at base

Diameter: 14 mm
Die Orientation: 12 H
Weight: 1.79 g
Publius Carisius as legatus
RIC I (Second Edition) Augustus 1b
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An AR Quinarius struck c. 25-23 BC in Emerita
Obverse: bare head right; AVGVST

Reverse: Victory standing right, placing wreath on a trophy consisting of helmet and cuirass; dagger and sword hilt at base of trophy; P CARIS_I__LEG

Diameter: -
Die Orientation: -
Weight: 1.56 g
P. Carisius, legatus pro praetore
RIC 1a; sear5 1642; RSC 386
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An AR Quinarius struck 214 AD in Rome
Obverse: ANTONINVS PIVS AVG GERM, Bust of Caracalla facing right, wearing laurel wreath, cuirass, and drapery

Reverse: COS IIII P P, Victory advancing left, holding wreath and palm

Diameter: 15 mm
Die Orientation: 12 H
Weight: 1.27 g
No notes for this coin
RIC IV Caracalla 317a
(4) Galba
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An AR Quinarius struck 68-69 AD in Lugdunum
Obverse: SER GALBA IMP CAESAR AVG P M T P, Head of Galba facing right, wearing laurel wreath

Reverse: VICTORIA GALBAE AVG, Victory wearing drapery, standing facing left on top of globe, holding wreath and palm

Diameter: 16 mm
Die Orientation: 6 H
Weight: 1.62 g
No notes for this coin
RIC I (Second Edition) Galba 131