The Early Republic: Bronze Money for a Growing State

Before Rome became a Mediterranean superpower, most transactions were conducted using bronze. The earliest Roman money consisted largely of bronze valued by weight. By the third century BC, Rome was producing large cast bronze coins known as aes grave, meaning "heavy bronze." These impressive pieces often weighed several ounces and formed the foundation of the Republic's early monetary system. The most important denomination was the As, which would remain a key part of Roman currency for centuries.

The As

The As was a bronze coin that served as the basic unit of Roman money. As Rome expanded, the weight of the As gradually decreased, making it more practical for everyday commerce. By the late Republic, it had evolved from a large cast bronze piece into a much smaller struck coin. For ordinary Romans, the As was one of the coins most commonly used for daily purchases.

The Silver Revolution: The Denarius Arrives

Around 211 BC, during the struggle against Carthage in the Second Punic War, Rome introduced what would become its most famous coin.

The Denarius

The silver denarius quickly became the backbone of Roman commerce. For centuries it served as the standard silver coin of the Roman world. Soldiers were paid in denarii, merchants counted profits in denarii, and many of Rome's most famous coin designs were struck on denarii. When collectors imagine Roman silver coins, they are usually thinking of denarii. The denarius became so influential that its name survives in later currencies such as the dinar, used in parts of the modern Middle East and North Africa.

While these relationships evolved somewhat over time, they provide a useful framework for understanding Roman currency.

The Imperial Age: Rome's Classic Coinage

When Augustus became Rome's first emperor in 27 BC, he reorganized the monetary system into a structure that would remain recognizable for nearly three centuries. This is the system most collectors encounter today.

The As

The humble bronze As continued to circulate as Rome's basic small change.

The Dupondius

Worth two asses, the dupondius was usually struck in a yellowish brass alloy called orichalcum.

The Sestertius

Worth four asses, the sestertius became one of the most impressive coins in Roman history. Large, heavy, and often beautifully engraved, sestertii feature some of the finest portraits ever produced by Roman mints. Their large size allowed engravers to create remarkable detail, making them favorites among collectors today. Many of the most famous coins of Augustus, Nero, Trajan, Hadrian, and Marcus Aurelius survive on sestertii.

The Denarius

The silver denarius remained the primary silver denomination of the empire. For much of the first and second centuries AD, it represented stability and prosperity. These centuries are often considered the golden age of Roman coinage.

The Aureus

At the top of the system stood the aureus, Rome's principal gold coin. Gold aurei were valuable pieces typically used for large transactions, military payments, and state finances. Because of their purchasing power, far fewer survive than bronze coins. Today, aurei rank among the most desirable and valuable Roman coins.

Crisis and Inflation: The Third Century Changes Everything

The third century AD brought invasions, civil wars, economic instability, and dozens of rival emperors. The Roman monetary system struggled to keep pace.

The Antoninianus

Introduced by Emperor Caracalla around AD 215, the antoninianus was intended to function as a coin worth roughly two denarii. The problem was that it did not contain twice the silver. Over time, successive emperors reduced the silver content even further. Under rulers such as Gallienus and Claudius II Gothicus, the silver content fell dramatically, and many antoniniani became little more than bronze coins covered with a thin silvered surface. This debasement contributed to inflation throughout the empire.

For collectors today, antoniniani are among the most affordable Roman silver coins and often feature fascinating portraits from one of Rome's most chaotic eras. Emperors such as Gallienus, Claudius II Gothicus, Aurelian, Probus, and numerous usurpers are commonly collected through their antoniniani.

Reform and Recovery: Diocletian and Constantine

By the late third century, Rome's monetary system needed a complete overhaul. Emperor Diocletian and later Constantine introduced major reforms that transformed Roman coinage.

The Follis

Diocletian introduced a large bronze coin commonly referred to by modern collectors as the follis. Early examples were impressive pieces with a thin silver coating and substantial weight. Over time, however, they gradually became smaller and lighter. Many collectors encounter folles from the reigns of Diocletian, Maximian, Galerius, and Constantine.

Late Roman Bronzes

During the fourth century, Roman bronze coinage evolved into the smaller coins often seen in beginner collections today. Because millions were struck and many survived, these coins remain among the most affordable authentic artifacts from the ancient world. For many collectors, they serve as the perfect introduction to Roman numismatics.

Understanding AE1, AE2, AE3, and AE4

New collectors often encounter terms such as AE1, AE2, AE3, and AE4. These are modern numismatic classifications based on the size of late Roman bronze coins rather than their ancient names or denominations.

While the Romans themselves did not use these terms, modern collectors and auction houses frequently do, making them useful labels to understand when shopping for ancient coins.

The Solidus: Rome's Last Great Coin

During the reign of Constantine in the early fourth century, a new gold denomination emerged that would outlast the Western Roman Empire itself.

The Solidus

The solidus became one of the most successful coins in world history. Unlike many earlier denominations, the solidus maintained remarkable consistency in weight and purity. It quickly became the preferred gold coin across the Mediterranean. Even after the fall of the Western Roman Empire in AD 476, the Eastern Roman, or Byzantine, Empire continued striking solidi for centuries. The coin became an international standard of trade, influencing monetary systems far beyond Rome's borders.

Many historians consider the solidus one of the most successful currencies ever created.

Which Roman Coins Are Best for Beginners?

If you are just starting out, it helps to focus on denominations that are affordable, historically important, and widely available.

These coins offer a direct connection to some of the most important figures and events in Roman history without requiring a large investment.

The Legacy of Roman Money

Over more than a thousand years, Rome created one of the most influential monetary systems the world has ever known. The bronze As of the Republic, the silver denarius of Caesar's age, the great sestertii of the emperors, the antoniniani of the Crisis of the Third Century, and the solidi of Constantine each tell the story of a changing empire.

For collectors, understanding these denominations does more than explain coin values. It provides a roadmap through Roman history itself. Every Roman coin represents a moment in that journey. Learn the denominations, and you will begin to see not just individual coins, but the evolution of Rome through the money its people used every day.

History wasn't just written. It was minted.