Tetarteron: History of the Byzantine Gold / Copper Coin

Illustrated Specimen Details: Byzantine Tetarteron

Example Specimen: Copper Tetarteron, 1143-1180 (Byzantine Empire)

Iconography & Origin: This copper tetarteron was struck during the reign of Manuel I Komnenos (Porphyrogennetos, meaning "born in the purple"), Byzantine emperor from 1143 to 1180, at the Thessalonica Mint in Macedonia (nowadays Greece). The obverse features the Emperor holding the attributes of power: a labarum (military standard or state flag of imperial Rome) and a globus cruciger (the orb and cross, a spherical symbol of monarchical power). The poorly preserved legend around the figure of Manuel I approximately reads MANƔHΛ ΔЄCΠΟΤ or MANOVHΛ DЄC (Ruler or lord Manuel). The reverse depicts Saint George (Greek Γεώργιος) with a nimbus, tunic, and cuirass, holding a spear and shield, accompanied by fragments of the inscription ΓΕΏΡΓΙΟΣ.

1. BYZANTINE EMPIRE (10th-13th centuries): tetarteron = 1/864 hyperpyron

About the name: The name of the coin most likely derives from the Greek word "τέταρτο" (tetarteron), meaning "quarter" or "fourth part". Originally, upon its emergence, this name referred to the coin's value as equivalent to one-fourth of the golden Byzantine solidus (nomisma), although its actual monetary relationship changed over time.

The Tetarteron in the Byzantine Monetary System

The tetarteron was a Byzantine coin denomination used between the 10th and 13th centuries. While its name implies a "quarter", its role became increasingly complex as it navigated through various Byzantine currency reforms. In later Byzantine accounting, the mathematical relationship was established at 1 tetarteron equal to 1/864 hyperpyron, forming part of an intricate hierarchy of gold, silver, and copper currencies.

Historical Context and Physical Evolution

The tetarteron was first introduced in the 10th century during the reign of Emperor Nikephoros II Phokas. Originally, it was struck in gold as a slightly lighter-weight coin issued alongside the standard histamenon nomisma. The exact reason for its introduction remains a subject of historical debate, but it was likely tied to taxation reforms, fiscal policy, and the need to differentiate between coin standards.

Over the centuries, the denomination evolved substantially. By the Comnenian period and later Byzantine eras, the gold tetartera had entirely transformed into a common copper coinage. These later copper tetartera were often small, thick, and more crudely struck compared to the earlier gold issues. Their designs consistently featured Byzantine imperial and religious symbolism, including portraits of Christ, emperors holding crosses or globes, and Greek religious inscriptions.

Economic Role and the Hyperpyron Standard

As the hyperpyron became the principal Byzantine gold coin following the sweeping reforms under Emperor Alexios I Komnenos, the tetarteron shifted from a precious metal issue to a fractional denomination. It served as a practical, everyday circulation coin, representing the empire's evolving response to economic decline and currency debasement.

Key Point

The tetarteron was a versatile Byzantine denomination originally introduced as a lighter gold coin and later transformed into a mass-produced copper currency. Valued eventually at 1/864 of a hyperpyron, these coins are essential for studying imperial monetary reforms and the economic history of medieval Byzantium.