The Coin Reform of the Byzantine Emperor Alexius I, 1081-1118.

Alexius I is most famous for being the Byzantine emperor during the First Crusade which began in 1096. Also, he was the first emperor of the long and largely successful Comnenid dynasty. Numismatically, he is important for reforming the Byzantine coinage in 1092.  All the old denominations in gold, silver, and copper were no longer issued and new denominations were created. 

Upper right: The new "hyperpyron" gold denomination issued by Alexius I. This example is 31 mm, 4.34 grams, slightly cup-shaped, and, like most examples, is somewhat wrinkly. The denomination is too thin and easily bent.
The obverse has Christ seated facing and the reverse has Alexius standing facing, crowned by the hand of God, with exaggerated jewels on his elaborate robe. Sear 1913. (The essential reference is David Sear's Byzantine Coins and their Values, second edition.) For more details, including the legends, see below.

This page is part of a larger site, "Introduction to Byzantine Coins." You may wish to begin there.
Contents of this page:

   Post- and pre-reform gold coins
   Table outlining the coin reform
   Pre- and post-reform copper coins of Alexius 
   Table of emperors before the reform--Constantine X (1057-1067) to Alexius I (1081-1118).
   Copper coins of emperors before the reform
   More about gold coins

All images are to scale.
Byzantine copper coins are very collectable and inexpensive. You may skip down to the copper coins of Alexius I and earlier emperors


Changes in the gold in the reform of Alexius in1092
 The previous histamenon   The new hyperpyron
less gold, 7-10 carats  more gold, 20 1/2 carats
smaller diameter, c. 28 mm broader "spread fabric" c. 31 mm
thicker and stronger  thinner
less likely to be bent easily bent or wrinkled
a cup-shaped "trachy" still cup-shaped, but less so


Pre-reform gold:  To the right is a pre-reform lower-quality gold "histamenon" of Emperor Romanus IV, Diogenes (1068-1071. Sear 1861).  Romanus IV is most famous for losing the disastrous Battle of Manzikert in 1071. It greatly weakened the empire by ceding to the Seljuq Turks the east and the central plateau of modern Turkey.
This example is 28-24 mm and 4.28 grams. Its paler color shows its lower gold content--maybe 10 carats.  The older cup-shaped type shown here is not so thin and rarely wrinkled, but it is often clipped to harvest gold from the rim. Collectors should pay attention to the diameter and weight. Coins lighter than this one are probably clipped. 

Although issued by Romanus IV, the obverse shows figures of the three young sons of the previous emperor Constantine X (1059-1067) and his wife Eudocia. It confirms their sons were still the designated heirs. The obverse legend abbreviates their names left-to-right, Constantius, Michael (the oldest, who became Michael VII) and Androncius. After the death of her husband and a short sole reign as regent, Eudocia married Romanus IV, a prominent general. The reverse has Christ in the middle crowning Romanus on the left and Eudocia on the right.  


The Coinage Reform of Alexius I in 1092
   Before the reform    After the reform
"Histamenon" of 28 mm and 7 carat gold (cup-shaped) [example above]
"Electrum tetarternon nomisma" (small, thick, and flat) [no example]

"Hyperpyron" of 31 mm and 20 1/2 carat gold (cup-shaped) [example above] The word means "highly refined" (literally, "above fire") which refers to the quality of gold.
"Electrum aspron trachy" c. 6 carats fine (cup-shaped) = 1/3 hyperpyron. [no example]
Silver: (all rare) [no examples here]
miliaresion (cup-shaped)
2/3 miliaresion (flat)
1/3 miliaresion (flat)
No denomination is close to pure silver.
The cup-shaped "billon aspron trachy" is of very base silver and sometimes shows some silver [example below], but usually looks like copper 
Copper (all flat)
Anonymous folles of Classes J and K [examples below]
Named folles [examples below]

"Tetarteron" of 18-22 mm.* [examples below]
"Half-tetarteron" of c. 16 mm. 

Coins with the "cup shape" are now called "trachy." Some authors call them "concave." They used to be called "scyphate" but that has been shown to be a misunderstanding of the term. 
Unfortunately, the term "tetarteron" refers to two very different Byzantine denominations. It can be a gold piece or a small base-metal coin.

The word "tetarteron" means "a fourth part." Earlier the term "tetarteron" was used for a gold piece (initiated under Nicephorus II, 963-969) which was very much like a solidus, but reduced in weight by one-quarter of a tremissis. So, it had 11/12 the gold of a solidus. (Yes, that seems odd.) With gradual debasement it morphed into a silver coin. With the reform the term "tetarteron" switched meaning to apply to the new small base-metal coin (perhaps one quarter of a follis?) We use it for both the no-silver and low-silver issues, which are difficult to distinguish. The one thing that remains constant about coins called tetartera is their flat shape. To avoid the inevitable confusion, the gold coin should be called a "tetrarteron nomisma" leaving the term "tetarteron" to the small post-reform copper denomination. 

*DOC distinguished the Constantinople issues and the Thessalonica issues of tetartera because of the small silver content in the Constantinople issues. Papadopoulou notes they had different circulation patterns. It is rare to find a tetarteron with any evidence of silver remaining, but some show some silver on the surface. The hyperpyron and the electrum aspron trachy also had different circulation patterns. The electrum aspron trachy was called a "trikephalon" (three-header) at the time because its initial type had one figure on one side and two on the other for a total of three, as opposed to the hyperpyron which had only two.   



Pre-reform copper of Alexius.  Alexius issued both "anonymous" and "named" pre-reform copper types. All are flat. Two types of anonymous folles, Classes J and K, are attributed to Alexius.

Class J is distinguished by the large crescent below the cross on the reverse. 
This piece: 24-22 mm. 7.09 grams.
Bust of Christ facing.
Cross with large pellets at ends, crescent below. 
Sear 1900, overstruck on Sear 1888 of Nicephorus III (1078-1081).



Class K is distinguished by the borders of large pellets.
This piece: 25-22 mm. 6.92 grams.
Bust of Christ facing, IC XC either side, inside a rim of large pellets. 
3/4-length figure of Mary standing, orans, facing, inside rim of large pellets. 
Sear 1901.


Alexius named pre-reform folles
This piece: 25-23 mm. 5.82 grams.
NI KA in the arms of a square cross with bars above indicating abbreviations 

CЄP CVN     Savior, assist
ЄPΓЄI BA      em/peror
CILЄI AΛ        Al/exius 

These are usually close to illegible. The letters are not well-formed.  
Sear 1911. 


The next pre-reform follis type of Alexius is much scarcer.

This piece: 25-23 mm. 3.68 grams.
Facing bust of the Virgin Mary, MP ΘV either side
holding medallion of Christ
Alexius standing holding labarum and globus cruciger
AΛЄ ...  for Alexius, beginning at 7:30.
Sear 1909

The new post-reform low-denomination coins.  Prior to the reform the low-denomination coins were flat and only the electrum coins and the miliaresion were cup-shaped. Alexius added in a cup-shaped "billon aspron trachy" with a small amount of silver in its alloy, valued at 1/48 of a hyperpyron.
This example: 26-24 mm and 4.28 grams. Unusually silvery. 
Christ enthroned facing. Half-length figure of Alexius facing. Sear 1918.
Most coins of this denomination look like copper. Alexius, and only Alexius, has some that still look silvery. 


A new copper "tetarteron".  The previous follis was a larger coin of c. 24 mm and c. 6 grams. It was replaced by the smaller tetarteron. 
Alexius I, 1081-1118. Tetrarteron.

This piece: 18 mm. 3.93 grams.
Half-length bust of Christ facing, IC XC on either side. The reverse has a half-length bust of Alexius facing. AΛЄ beginning "Alexius" to his left. 
Sear 1920.

Prior to the reform each emperor issued only one or two types of copper coins, In contrast, the new tetarteron denomination comes with numerous types and the new half-terarteron is distinguishable from them only by being smaller.

Here is a second, common, type of the new tetarteron
Alexius I, 1081-1118. Tetrarteron.
This piece: 20-18 mm. 3.71 grams.
Emperor facing with cruciform scepter and globus cruciger

Reverse with, in the quadrants of a jeweled cross:
C   Φ   (The "C" is a lunate "S" (sigma))   
            ΣΤAYΡЄ  ΦΥΛATTЄ   "O Cross, Protect"
AΛ  Δ    [The "AΛ" for "Alexius" looks like an "M"--the crossbar of the A is missing] 
           AΛЄΞION ΔЄCΠOTH. "May the cross protect   (or, O Cross, protect) Alexius Despot"

History and Coins Outline:

Byzantine Emperors 1059-1118


Dates Relationship to the previous emperor Gold coins Silver Copper coins
Anonymous Classes
Named types
Constantine X and
his wife Eudocia
1059-1067 None. He was a relative of the patriarch who was
selected when the populace overthrew Isaac I 
because of his ill-treatment of the patriarch.
Common Rare Classes E & F
Sear 1853 & 1854
Eudocia May-Dec 1067 Wife. When Constantine X died she became
regent for their son Michael [later Michael VII].
Rare (They do not have her portrait) none none (Her standing figure is on the common Sear 1853)
Romanus IV 1068-1071 General. He married Eudocia because foreign attacks required a general.  Common Rare Class G
Sear 1866
Michael VII 1071-1078 Eldest son of Constantine X and Eudocia.
Still too young and under the influence of his advior Psellus
Common Rare Class H
Sear 1878
Nicephorus III 1078-1081 General who successfully rebelled and became emperor. Common Rare Class I
Sear 1888
Attempted usurpers.
Nicephorus Bryennius &
Nicephorus Basilacius 

Oct. 1077 - May 1078

May-July 1078 

Generals who rebelled with only regional success. None



Bryennius: Rare, but some on the market recently. Sear 1980

Basilacius: Very rare, but some on the market recently.
Alexius I 1081-1118 General of Nicephorus III. Alexius put down the two revolts mentioned above, but joined a third and became emperor. Common Rare Classes J and K 
Pre-reform: Sear 1909, 1911
Post reform: several types


About copper.  The classes of anonymous folles mentioned in the rightmost column are discussed on their own page.  In this time period each emperor before Alexius had only one or two copper types with his name. They are illustrated next.

Constantine X, Ducas (1059-1067) came to the throne when Isaac I was deposed by the populace angry at his religious policies. His wife was Eudocia and his copper coins depicting him and his wife are common (although rarely in excellent condition). 

Constantine X, Ducas (1059-1067). One of only two copper types. Sear 1853.
This piece: 29-28 mm. 10.58 grams.

Christ standing, +ЄMMA-NOVHA around "God is with us"

Constantine X and Eudocia standing
Unusually, the reverse legend begins at 2:00:
That is,
KωN[Σ]Τ[ΑΝΤΙΝΟΣ O] Δ[ΟY]Κ[ΑΣ] [ЄΥΔ[Ο]Κ[ΙΑ] ΑYΓ[ΟΥΣΤΟΙ] Constantine (the) Doukas, Eudocia, Augusti [or, emperors] 



Constantine X, Ducas (1059-1067).  His other named copper type. Sear 1854.
This example: 27-25 mm. 8.82 grams.
Bust of Christ facing. 
Half-length figure of Constantine facing, holding labarum

KωN RACIΛVCOΔOK  ("R" is "B" beginning "Basileus" for "emperor," "O" is for "the", and "ΔOK" is for Ducas, his family name.

When Constantine died in 1067 the empire was under attack from all sides. He and Eudocia had three sons, but even the oldest was not old enough to be emperor alone. Eudocia became both sole empress and regent for seven months. She was pressed into marrying the general Romanus IV who acknowledged her sons as heirs. The three sons are on the obverse of the gold histamenon of Romanus IV above


Romanus IV (1068-1071). His only named follis type.
Sear 1866.
This example, 31-29 mm (larger than usual). 5.32 grams.
Bust of Christ facing
  in small letters either side of the head
The reverse has a square cross with 
C  R
P  Δ
   (The "C" is a lunate "S" (sigma)).   ΣΤAYΡЄ  ΦΥΛATTЄ   "O Cross, Protect
Romanus Despot/emperor"   RΩMANΩ  ΔЄCΠOTH

Anonymous folles of Class G are attributed to Romanus IV.



When Romanus IV lost the Battle of Manzikert he was captured by the Seljuq sultan Arp Arslan, who, after obtaining significant concessions, released Romanus to go home. It was a master stroke, splitting the Byzantines into opposing camps. The remains of the army had already promoted Michael VII, Ducas--the proper heir, the son of Constantine X we saw on the obverse of the coin of Romanus IV--to emperor not long after the battle. When Romanus was unexpectedly released and returned to Constantinople he found it already had a new emperor. Constantinople was in possession of the Ducas family of Constantine X and his young son Michael VII (who was really under the control of his advisor Psellus who wrote the extant book Fourteen Byzantine Rulers). Romanus lost his bid to reclaim the throne, was blinded, and sent to a monastary in 1078.

Michael VII, Ducas (1071-1078). His only named follis type. Sear 1878.
This example. 25 mm. 9.63 grams (thicker and heavier than typical)
Bust of Christ facing, IC XC either side
Large stars in each field
Facing bust of Michael VII, holding labarum and globus cruciger.

Anonymous folles of Class H are attributed to Michael VII. 


Nicephorus III (1078-1081) successfully rebelled against Michael VII who retired to a monastary. Two revolts against Nicephorus were put down by his general Alexius Comnenus, but when Alexius' brother in law revolted Alexius marched with him to Constantinople and Nicephorus wisely retired to a monastary and Alexius took the throne as the first of the long and successful Comnenid dynasty. 

Nicephrous III, Botaniates (1078-1081). His only named follis type.
Sear 1888. 
This example: 23-22 mm. 5.55 grams.
3/4 length figure of Christ, IC XC either side, stars in fields

C  Φ     (The "C" is a lunate "S" (sigma).)   ΣΤAYΡЄ  ΦΥΛATTЄ   "O Cross, Protect"
N  Δ   "Nicephorus [III] Despot/emperor"  NIKHΦωPON  ΔЄCΠOTH

Anonymous folles of Class I are attributed to Nicephorus III. 

Nicephorus III was followed by Alexius I whose copper coins were discussed above

 Nicephrous Bryennius (May - July 1078). One of the usurpers during the reign of Nicephorus III. The attribution of this type has been uncertain for decades. Now Kevin Parsons argues it was struck in under Nicephorus Bryennius. 
Sear 1890 (attributed there to Nicephorus Basilacius).
This example: 26-24 mm. 4.18 grams.
Bust of Christ facing, IC XC either side
Elaborate patriarchal cross with X at center and
C  B
N  B in its quadrants.
Formerly thought (by Hendy and Sear) to be of the other usurper named Nicephorus, Nicephorus Basilacius, but Grierson argued it was of Bryennius and the recent work of Parsons confirms it. 
This type was considered extremely rare until c. 2018 when examples began to appear on the market. 

Aside:  The emperor Nicephorus Botaniates and the two usurpers Nicephorus Basilacius and Nicephorus Bryennius all had initials "NB". This coin, with "NB" in the lower quadrants is not explict about which one it is. Arguments about its attribution took into account findspots and overstrikes.


History of Byzantine gold coins. The quality of the gold in Byzantine "gold" coins declined from nearly pure (24 carats) to about 7 carats fine in the 50 years prior the reform of Alexius. Here is a simplified history of the gold coinage up to the reform.

  • 315-963.  The gold solidus remained essentially unchanged in size and purity of gold from its introduction by Constantine c. 315 until Nicephorus II (963-969).
  • 963 ff       Nicephorus II made two gold denominations to replace the solidus. One, the "histamenon nomisma" or just "histamenon," had the gold value of a solidus but soon became larger in diameter and thinner--of "spread fabric." It began c. 21 mm, but became 23 mm and then 26 mm in the next reign, Basil II (969-1025). 
           The second gold denomination maintained the diameter and appearance of a solidus but was thinner and lighter.  We might call it a light-weight solidus. It is called the "tetarteron nomisma" or just "tetarteron" and is still c. 20 mm. The word "tetarteron" means "a fourth part," which refers to the standard weight reduced by one fourth of a temissis, so the new tetarteron is valued at only 11/12 of a solidus. (Later the term "terarteron" refers to something much different--a small copper denomination introduced by Alexius I.) In spite of their similar gold values, both denominations continued to be issued until the reform of Alexius I in 1092.
  • 1030s    The gold coins remained close to pure until Michael IV (1034-1041), when an initial drop to 20 carats began a 50-year decline to c. 7 carats. Also, the histamenon began to be slightly cup-shaped. When coins are cup-shaped we use the term "trachy" (sometimes "concave") to describe the shape, modified by the the name of the denomination or the metal (e.g. "Billon aspron trachy").  
  • 1092     Alexius I (1081-1118) reformed the coinage. The copper follis and old electrum denominations were discontinued and new denominations issued.  

Next are gold coins with more details about their types.

Romanus IV (1068-1071) histamenon. [Also illustrated above]
28-24 mm and 4.28 grams.

The obverse legend abbreviates their names, KωN at 8:00 for Constantius, MX at 1:00 for Michael (later Michael VII) ) and ANΔ at 3:30 for Androncius (not the later emperor of that name).

The reverse shows Christ in the middle crowning Romanus on the left and Eudocia on the right. The legend is 
PωMAN ЄVΔKIA for Romanus and Eudocia.

Sear 1861.



Michael VII (1071-1078) histamenon.
28 mm. 4.24 grams. Slightly clipped as can be seen 11:00-1:30 on the obverse.
Bust of Christ facing. IS XC either side. No legend.
Michael VII facing, holding labarum and globus cruciger.
"Michael, Emperor, Despot"

He was a minor when he became emperor. The coin portrait makes him look older than he was. 


Alexius I (1078-1118) hyperpyron. [Also illustrated above]
Sear 1913.
This example: 31 mm. 4.34 grams.
Christ seated facing, holding gospels in his left and right hand raised in benediction.
Alexius I standing (vertically exaggerated) with elaborate imperial robes with greatly exaggerated jewels. He holds labarum and globus cruciger.
Legend either side:
 A               Tω
ΛЄ             KO
ZIω            MH
ΔЄC           Nω
"Alexius, Despot, Komnenus"




References: (In order of importance to this topic)


Byzantine Coins and their Values, second edition, 1987, by David Sear. 

Catalogue of the Byzantine coins in the Dumbarton Oaks Collection and in the Whittemore Collection, volumes 3 (1973) and 4 (1999). Alexius I is in volume 4, part 1, pages 181-243, with plates I-VII in volume 4, part 2. Constantine X through Nicephorus III are in volume 3, part 2, which includes both text and plates.

Byzantine Coins, by Philip Grierson. 1982. Alexius I is discussed on pages 211-228 with images on plates 59-62. 

Fourteen Byzantine Rulers, by Michael Psellus (1018-1096) translated by K.R.A. Sewter, in the Penguin Classics series. 1966. A primary ancient source.

A Short History of Byzantium, by John Julius Norwich. 1997. A very entertaining 431-page condensation of his three-volume series on Byzantium. I recommend this shorter version for beginners and the longer version if you become more interested. Unlike many other history books on the Byzantine empire, this one focuses on stories about the emperors, with less on administration, the Church, organization of the army, and structure of the government. In other words, it is just what coin collectors want!

Hendy, Michael. Coinage and Money in the Byzantine Empire, 1081-1261. 1969. 453 pages, 51 plates, and two large pull-out maps. Pages 1-101 cover the monetary crisis through the reform coins of Alexius I. 

Papadopoulou, Pagona. "The big problem of small change in the Byzantine world (12th-13th centuries)." The First International Byzantine Studies Symposium, Proceedings. 2010. 

Parsons, Kevin. 2022. Manuscript under review. 


After I posted about Alexius to CoinTalk, there were several interesting replies

Return to the page "Introduction to Byzantine coins." 

Contact me at