Roman coin identification: dating small, worn bronze coins

A Roman coin from a British field is usually small, bronze and worn.

Don’t throw them in the scrap tub. Most can be dated to within a few years, from the reverse alone.

How common are they?

Very. Richard Henry’s corpus in Britannia (2024) counts 490,154 Roman coins found as site finds in England and Wales, from the PAS, excavations and other studies.

Archaeologists split Roman coins into 21 issue periods, called Reece periods, running from before AD 41 to AD 402. The PAS has added two more for the fifth century.

The four big groups

Henry’s paper groups the coins into broad phases. They make a good field key.

Phase D is the big one. Coins of AD 330–348 (Reece period 17) are the most numerous of any period.

Phase A: the early Empire, to AD 260

The early system used gold, silver and copper alloy. The silver coin was the denarius. The bronzes were the sestertius, dupondius and as: big, heavy coins.

They stayed in use a long time. Henry notes these coins could circulate for 100 years or more, partly because the supply of bronze to Britain fell sharply around AD 196. So a worn sestertius may have been lost long after it was struck.

Phase B: radiates, AD 260–296

A radiate shows the emperor wearing a crown of spikes. It was introduced by Caracalla in AD 215 and brought back in 238, and it replaced the denarius.

When the old system collapsed around AD 260, the radiate became the only common coin. In the 260s and early 270s it was heavily debased and struck in vast quantities.

Aurelian reformed it around AD 274, but the new coins didn’t reach Britain in quantity. Instead, barbarous radiates (unofficial copies) were made in large numbers. They turn up regularly on sites.

Phase C: the first nummi, AD 296–330

In AD 294 a new copper-alloy coin replaced the radiate. Its Roman name is uncertain; it’s conventionally called the nummus. It started at a little over 10 g and shrank in a series of reforms, to about 2.5 g by AD 317.

The main mints supplying Britain were London, Trier, Lyon and Arles. London struck coins until AD 325. After that, all coin was imported.

Phase D: the commonest coins, AD 330–364

This is the coin you’re most likely to find. The FLAME guide from Princeton lists the main types by reverse legend:

The falling horseman is easy to spot, even on a worn coin: a soldier with a spear, and a rider tumbling off his horse.

Phase E: the last supply, AD 364–402

Under the houses of Valentinian and Theodosius, the common reverses include:

• GLORIA ROMANORVM, emperor dragging a captive (364–378).
• SECVRITAS REIPVBLICAE, Victory advancing left (364–383).
• VRBS ROMA FELIX (394–395).

From AD 395, the mints north of the Alps stopped making nummi. After 402, very little new coin reached Britain.

How to read a worn Roman bronze

1. Measure and weigh it. A big, heavy coin is likely early. A tiny one is likely late.
2. Look at the crown. Spikes mean a radiate.
3. Read the reverse. Even three letters can narrow it down; use the tables above.
4. Check the figures. Two soldiers, a falling horseman or a camp gate are all distinctive.
5. Record it. Your Finds Liaison Officer can identify coins you can’t.

The PAS also publishes an introduction to Roman coins on its website.

Reporting

One coin usually isn’t Treasure (the exception is the 2023 class for finds of exceptional significance). Ten or more coins of any metal from the same find, or two or more with at least 10% precious metal, are Treasure if they’re over 300 years old. See what counts as treasure. In Scotland, all archaeological finds must be reported: see our Scotland guide.

For later coins, see hammered coins.

FAQ

What is a radiate?

A coin showing the emperor wearing a spiky radiate crown. It was first introduced by Caracalla in AD 215, reintroduced in 238 and soon replaced the denarius. In the 260s and early 270s it became very debased and was struck in vast numbers.

What are barbarous radiates?

Unofficial copies of radiates. After Aurelian's reform of around AD 274, the new coins didn't reach Britain in quantity, and copies were made in large numbers instead.

What does GLORIA EXERCITVS mean on a coin?

‘The glory of the army’. It shows two soldiers with standards. The two-standard version dates to AD 330–337; the one-standard version to 335–347.

Do I have to report Roman coins?

A single coin usually isn't Treasure. Ten or more coins of any metal from the same find, or two or more with at least 10% precious metal, are, if over 300 years old. Record single coins with the PAS through your Finds Liaison Officer.

Sources

Every figure in this guide comes from one of these. We checked each one on 1 November 2026.

1. Richard Henry, “A New Corpus of Roman Coins from England and Wales. An Overview of the Evidence and Analysis of the Data”, Britannia (Cambridge University Press, published online 25 October 2024). www.cambridge.org/core/journals/britannia/article/new-corpus-of-roman-coins-from-england-and-wales-an-overview-of-the-evidence-and-analysis-of-the-data/21B5675F3F8C51D63CC491E2E2FA0394
2. Ilia Curto Pelle, “FLAME’s Introduction to Classifying Roman Bronze Coins, c. 325–491 CE” (Princeton University, updated 28 February 2024). coinage.princeton.edu/wp-content/uploads/2024/03/FLAMEs-Introduction-to-Classifying-Roman-Bronze-Coins-c.-325-491-CE.pdf
3. Portable Antiquities Scheme, “An introduction to Roman coins”. finds.org.uk/romancoins
4. Treasure Act 1996 Code of Practice (3rd revision), GOV.UK. www.gov.uk/government/publications/treasure-act-1996-code-of-practice-3rd-revision