Roman Coin Denominations: The Names, the Metals, the Values
What were Roman coins called, and how did they fit together? The Romans ran a layered system of gold, silver, brass and copper that lasted, with constant reform, for more than six hundred years. This is the full list — every denomination a collector meets, what it was made of, what it was worth, and where it sits in the story — with a link from each one to its coins in the NumisLens catalog.
The main Roman coins, by metal: in gold, the aureus and later the solidus; in silver, the denarius, the radiate antoninianus, and the late siliqua; in brass and copper, the big sestertius and dupondius, the copper as, and the late follis. One aureus was worth 25 denarii; one denarius, four sestertii or sixteen asses. Most "Roman bronze coins" are really the brass and copper aes coinage below the silver.
How the system worked
The Roman denomination system is really three systems stacked on top of each other in time. The Republic built a coinage around the silver denarius and a family of bronze pieces; the Empire under Augustus fixed that into a tidy scheme of gold, silver, brass and copper; and the later Empire, battered by inflation, tore the whole thing up and rebuilt it around new coins. Learn the Augustan scheme first, because everything before and after is a variation on it. In that system one gold aureus was worth 25 silver denarii, and one denarius was worth 4 brass sestertii, 8 dupondii, or 16 copper asses, with smaller copper fractions below. It belongs to the mainstream of Roman Imperial coinage, and its roots are in the Roman Republican issues that came before.
One point clears up more confusion than any other. When people search for "Roman bronze coins" or a "Roman copper coin", they are usually looking at the aes coinage — the coins below the silver. But those were not all the same metal. The big sestertius and the dupondius were struck in orichalcum, a brass alloyed with zinc that comes out a warm golden colour; the as, semis and quadrans were struck in almost pure copper, which is redder and darker. Dealers call the lot "bronze" for convenience, but the metals differ, and once you have handled a few the colour alone will often tell you which denomination you are holding.
The gold coins
Gold was the top of the system, a store of value and a coin for large payments rather than daily use.
| Denomination | Metal | Value | Note |
|---|---|---|---|
| Aureus | Gold | 25 denarii | The principal imperial gold coin, about 7.8 g under Augustus, slowly reduced over the following centuries. Deeper: the aureus guide. |
| Solidus | Gold | — | Constantine's replacement for the aureus, struck at 1/72 of a Roman pound (about 4.5 g). It held its value for centuries and became the Byzantine standard. |
| Tremissis | Gold | 1/3 solidus | A small late-Roman and early-medieval third of a solidus, roughly 1.5 g, carried on into the successor kingdoms. |
The silver coins
Silver was the backbone of the working economy. The denarius is the coin the whole Roman world reckoned in for three centuries; the coins around it are its fractions, its multiples and its debased successors.
| Denomination | Metal | Value | Note |
|---|---|---|---|
| Denarius | Silver | 1/25 aureus | The standard silver coin from about 211 BC, first tariffed at 10 asses (the mark X) and later at 16. The workhorse of Roman money. Deeper: the denarius guide. |
| Antoninianus | Silver → billon | 2 denarii (nominal) | The radiate "double-denarius" introduced by Caracalla in AD 215, identified by the emperor's spiked crown. Debased to near-bronze during the third-century crisis. |
| Victoriatus | Silver | — | An early Republican silver coin introduced around 211 BC, about 3.4 g, named for the Victory crowning a trophy on its reverse. |
| Argenteus | Silver | — | A high-purity silver coin from Diocletian's reform of AD 294, about 3.4 g. Struck for only about a decade, so it is scarce. |
| Siliqua | Silver | — | The main silver coin of the late Empire, roughly 2–3 g, struck alongside the gold solidus in the fourth and fifth centuries. |
The bronze and copper coins
This is the "Roman bronze coin" most people mean, and where the brass-versus- copper distinction matters. The sestertius is the giant of the group and a collector favourite for the room it gives a portrait and a reverse scene; the as was the humble unit that priced a loaf of bread.
| Denomination | Metal | Value | Note |
|---|---|---|---|
| Sestertius | Brass (orichalcum) | 4 asses = 1/4 denarius | The large brass coin, often 25–35 mm across, and the best canvas in the Roman series for portraiture and reverse types. The one advanced collectors chase. |
| Dupondius | Brass (orichalcum) | 2 asses | A brass coin close in size to the as; the radiate crown or a specific portrait style is often what tells the two apart. |
| As | Copper | Base unit | The everyday copper coin around which the whole bronze system was reckoned. Redder than the brass denominations. |
| Semis | Copper | 1/2 as | A small copper half-as, much less common in the imperial series than the as itself. |
| Quadrans | Copper | 1/4 as | The smallest regular Roman coin, a copper quarter-as; usually anonymous, without an imperial portrait. |
The late Roman reforms
By the later third century AD the old system had collapsed under inflation, and the coins changed names and metal almost faster than the catalogues can track. The follis — a large bronze with a thin silver wash, introduced in Diocletian's reform of AD 294 — is the denomination to know here, but it shrank so steadily over the following decades that collectors and cataloguers often fall back on the size labels AE1 through AE4 rather than a confident denomination name. Alongside it ran a shifting cast of small bronze nummi, the reformed silver, and Constantine's gold solidus. The tidy Augustan ladder was gone; late Roman bronze is a puzzle of its own, and the follis guide untangles it.
Where to start collecting
For a first Roman coin, the honest advice is to start where the history is richest and the fakes are fewest. A common third- or fourth-century bronze — a radiate antoninianus or a late follis — can be bought in collectable grade for the price of a restaurant meal, and it puts a real imperial portrait in your hand. A Very Fine silver denarius of a mainstream emperor is the classic next step and the coin most collections are built on. The brass sestertius is the showpiece, priced well above the smaller bronzes for its size and its portraiture. Gold is a specialist purchase, and the most faked metal of all — buy it last, and buy it with a pedigree.
Whatever you start with, the skill that matters is telling one denomination from another by metal, size and portrait, which is the first move in attributing any Roman coin. The how to identify Roman coins guide walks through that process step by step, and every denomination above links to its own coins in the NumisLens catalog so you can see the real range of what survives.
Frequently asked questions
What are the names of the Roman coins?
In gold, the aureus and later the solidus; in silver, the denarius, antoninianus, quinarius and late siliqua; in brass and copper, the sestertius, dupondius, as, semis and quadrans, with the follis in late antiquity. The Republic also struck the silver victoriatus.
Were Roman coins bronze or copper?
Both. The sestertius and dupondius were brass (orichalcum); the as, semis and quadrans were copper. "Bronze" is a loose catch-all — the real metals differ, and the colour often shows it.
Which Roman coin is the biggest?
Among regular circulating coins, the brass sestertius, often 25–35 mm across. Its size makes it the best coin in the series for portraits and reverse scenes, and the one collectors prize most.
How much was a denarius worth?
Under the early Empire, one denarius was worth four sestertii or sixteen copper asses, and 25 denarii made one gold aureus. The ratios changed with later reforms and debasement.
References
- The Roman Imperial Coinage (RIC) — the standard reference for imperial denominations, mint by mint and reign by reign.
- Mattingly, H., et al. Coins of the Roman Empire in the British Museum (BMCRE).
- Sear, D. R. Roman Coins and Their Values. Spink — a working handlist that lays out the denominations and their market ranges.
- Online Coins of the Roman Empire (OCRE) — the open type corpus, searchable by denomination.