What Is a Tetarteron? The Byzantine Gold Coin That Challenged the Solidus
What Is a Tetarteron? The Byzantine Gold Coin That Challenged the Solidus
Introduced by Nikephoros II Phokas as a Lighter Gold Coin, the Tetarteron Split Byzantine Gold Into Two Standards, Then Reappeared Centuries Later as a Humble Bronze Coin.
The tetarteron was a Byzantine denomination introduced in the tenth century as a lighter gold coin alongside the traditional solidus, or nomisma.
Its creation marked a major change in a gold standard that had remained remarkably stable for centuries. Under Emperor Nikephoros II Phokas, the Byzantine government began issuing a slightly lighter gold coin while preserving the older full-weight nomisma. The two circulated side by side and eventually developed into visually distinct denominations.
Centuries later, the name tetarteron was revived for a very different type of coin: a small bronze denomination used in the Byzantine Empire after the monetary reforms of Alexios I Komnenos.
What Is a Tetarteron?
The tetarteron was originally a Byzantine gold coin introduced under Nikephoros II Phokas (AD 963 to 969). It was slightly lighter than the traditional gold nomisma.
The word tetarteron means roughly "a quarter less" or "a fourth part," though the exact reason for the name has been debated by scholars. The gold tetarteron was not literally worth one-quarter of a nomisma. Instead, it represented a reduced-weight gold standard.
Why Was the Tetarteron Introduced?
For centuries, Byzantine gold coinage had been based on the remarkably stable solidus introduced by Constantine the Great. By the tenth century, however, the empire created a second gold standard.
The lighter tetarteron may have been introduced for fiscal, accounting, or regional reasons, and scholars continue to debate the precise motivation.
How Did It Differ from the Nomisma?
- Nomisma Traditional full-weight gold coin
- Tetarteron Slightly lighter gold coin
At first the two looked very similar, which must have created practical difficulties. Over time, their appearance changed so that users could distinguish them more easily.
How Big Was a Gold Tetarteron?
Weights varied, but the gold tetarteron generally weighed slightly less than the full nomisma.
- Weight Roughly 4.0 grams, varying by period
- Metal Gold
- Diameter Similar to contemporary nomismata, though variable
Later Byzantine gold coinage underwent significant debasement, complicating exact comparisons across reigns.
What Appears on a Tetarteron?
Gold tetartera often featured the emperor and Christian imagery, including Christ, the Virgin Mary, crosses, and imperial portraits.
Like other Byzantine coins, they used religious imagery to reinforce the emperor's legitimacy and the Christian identity of the empire.
Why Did the Gold Tetarteron Disappear?
Byzantine gold coinage changed dramatically during the eleventh century. Repeated debasement weakened the old nomisma system, and the monetary reforms of Alexios I Komnenos in 1092 replaced it with a new gold coin called the hyperpyron.
The old gold tetarteron disappeared as part of this broader restructuring.
The Bronze Tetarteron
After the reforms of Alexios I, the name tetarteron was reused for a small bronze coin. This later bronze tetarteron had no direct metallic relationship with the earlier gold coin but inherited its name within the new Byzantine monetary system.
Bronze tetartera became common small change in the twelfth century.
Who Struck Bronze Tetartera?
Several Komnenian emperors issued bronze tetartera, including Alexios I Komnenos, John II Komnenos, and Manuel I Komnenos.
These coins often feature imperial portraits, crosses, saints, Christ, or the Virgin.
Why Are Bronze Tetartera Popular?
They are affordable, historically rich, and closely connected to the Crusades and the Komnenian restoration of Byzantium.
- Affordable Byzantine history
- Christian iconography
- Connections to the Crusades
- Distinctive medieval style
- Wide variety of types
Are Tetartera Rare?
Gold tetartera are considerably scarcer and more valuable than bronze examples. Bronze tetartera of the Komnenian period remain relatively common and accessible.
Rare rulers, unusual types, and strong preservation can command higher prices.
Collecting Tetartera
The tetarteron tells two different chapters of Byzantine monetary history: first as a lighter gold coin challenging the ancient solidus standard, and later as humble bronze small change after one of Byzantium's greatest monetary reforms.
Few coin names have traveled so far, from imperial gold to everyday bronze.
History wasn't just written. It was minted.
Frequently Asked Questions
What is a tetarteron?
The tetarteron was first a lighter Byzantine gold coin introduced in the tenth century and later the name of a bronze denomination after Alexios I's reforms.
Who introduced the gold tetarteron?
It was introduced during the reign of Nikephoros II Phokas in the tenth century.
Was the tetarteron one-quarter of a solidus?
No. Despite its name, it was not literally a quarter-value coin. The gold tetarteron was only somewhat lighter than the traditional nomisma.
Why was the name reused for bronze coins?
After Alexios I's monetary reforms, the term tetarteron was applied to a new bronze denomination within the restructured Byzantine system.
Can you still buy a Byzantine tetarteron?
Yes. Bronze tetartera are often affordable, while gold examples are scarcer and more valuable.
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