Byzantine Follis Coins: How to Identify and Collect Them
The Byzantine follis is one of the easiest ancient coin types for a new collector to learn. The large copper denomination introduced under Anastasius I in AD 498 often tells you its value directly on the reverse, and later examples can also reveal the mint, workshop, and even the emperor’s regnal year.
What Is a Byzantine Follis?
In modern numismatic usage, follis commonly refers to the large Byzantine copper denomination worth 40 nummi. Anastasius I introduced the reformed denomination in AD 498 as part of a major restructuring of Eastern Roman bronze coinage.
The reverse is normally dominated by a large Greek letter M. In Greek numerals, M represents 40.
The name “follis” is conventional. Ancient terminology is not always as straightforward as modern catalog labels suggest, but the term is firmly established among collectors.
What Do M, K, I and E Mean on Byzantine Coins?
They are denomination marks:
- M = 40 nummi
- K = 20 nummi
- I = 10 nummi
- E = 5 nummi
The AD 498 reform initially established the larger marked denominations, while the five-nummi piece was added during Anastasius’ later enlargement of the bronze system around AD 512/513.
Why Did Anastasius Reform Byzantine Bronze Coinage?
Late fifth-century Eastern Roman bronze circulation relied heavily on very small nummi. Anastasius created larger denominations with clear value marks, making substantial base-metal payments more practical.
The first reformed folles were smaller than many later examples. The bronze standard was enlarged during Anastasius’ reign and changed repeatedly under later emperors.
There is therefore no single correct weight or diameter for every Byzantine follis.
How Do You Read a Byzantine Follis?
A sixth-century follis can provide several pieces of information:
- Emperor: usually identified from the obverse portrait and legend.
- Denomination: the large M means 40 nummi.
- Regnal year: many later folles show the emperor’s year of rule, often introduced by ANNO.
- Mint: an inscription in the exergue can identify Constantinople, Nicomedia, Cyzicus, Antioch/Theoupolis, and other mints.
- Officina: a letter can identify the workshop within the mint.
What Does ANNO Mean?
ANNO introduces a regnal-year date. Dated bronze coinage became a prominent feature under Justinian I.
Instead of giving a modern calendar year, the coin states the year of the emperor’s reign. Once the emperor’s accession date is known, the issue can often be converted to an approximate AD date.
Justinian I and the Classic Large Follis
Justinian I, who ruled from AD 527 to 565, issued some of the most famous Byzantine folles.
In his regnal year 12, AD 538/539, a major copper reform introduced larger and heavier folles along with a new facing imperial portrait at Constantinople and other mints. These broad pieces are among the most visually impressive affordable Byzantine coins.
Weight and diameter still vary, so a collector should use mint, year, portrait, legends, and denomination marks together rather than identifying a coin by size alone.
Common Byzantine Follis Mints
Depending on ruler and period, collectors can encounter folles from:
- Constantinople
- Nicomedia
- Cyzicus
- Antioch, renamed Theoupolis
- Thessalonica
- Carthage
- Ravenna
- Other imperial mints
Mint abbreviations vary by period. For example, Constantinople often appears as CON, while Antioch/Theoupolis can use forms such as THEUP.
Can You Collect Byzantine Folles by Year?
Yes. Dated issues make this one of the most structured areas of affordable ancient coin collecting.
You can build sets by emperor, mint, regnal year, officina, denomination, or combinations of those features. Justinian I is especially popular because his long reign and extensive mint system provide many possibilities.
Did Byzantine Folles Keep Getting Smaller?
No. The bronze system changed repeatedly. Some periods saw reductions, while reforms could also increase the size and weight of a denomination.
The familiar large-M follis also did not remain unchanged throughout Byzantine history. Later centuries developed different bronze systems and coin types.
Are Byzantine Folles Expensive?
Many common examples are affordable because substantial numbers survive. Rarer rulers, mints, years, varieties, exceptional portraits, attractive patinas, and high-grade examples can cost considerably more.
For beginners, a common follis with a readable M, identifiable emperor, and visible mint or date can provide a large amount of historical information for the price.
Frequently Asked Questions
Who introduced the Byzantine follis?
Anastasius I introduced the reformed 40-nummi denomination in AD 498.
What does M mean on a Byzantine coin?
M is the Greek numeral for 40 and marks the 40-nummi denomination conventionally called a follis.
What does ANNO mean on a Byzantine coin?
It introduces the emperor’s regnal-year date.
Are Byzantine folles good first ancient coins?
Yes. Common examples are often affordable, physically substantial, and unusually easy to study because denomination, mint, and dating information can appear directly on the coin.
Is every Byzantine bronze with an M a coin of Justinian?
No. The M denomination mark was used under many emperors. The portrait, legends, mint, regnal year, officina, and other details determine the attribution.
Final Thought
Byzantine folles reward close looking. What first appears to be a large, rough bronze can contain an emperor, denomination, mint, workshop, and date in a single design.
That combination of affordability and readable historical information makes the follis one of the strongest entry points into Byzantine coin collecting.