A Remarkable Discovery: Five-Pound Ingot of Egyptian Blue Found in Nero’s Palace

Unearthing Ancient Pigments in the Domus Aurea

Archaeologists excavating the ruins of Nero’s grand Domus Aurea in Rome have uncovered an extraordinary find—a massive chunk of Egyptian blue, one of history’s most prized pigments. This discovery sheds new light on the artistry and craftsmanship that adorned the emperor’s palace nearly 2,000 years ago.

Within the remains of ancient workshops, researchers found a collection of pigments stored in amphorae and small jars, including yellow ocher and reddish hues like realgar and red ocher. They also identified basins where artisans would have mixed the pigments with water before applying them to frescoes. However, the most astonishing find was a solid, six-inch-long, five-pound ingot of Egyptian blue—an exceptionally large sample of this rare, synthetic pigment.

The Significance of Egyptian Blue

Unlike natural pigments such as ocher and realgar, Egyptian blue was the world’s first known synthetic pigment. Made by heating a combination of silica, limestone, and copper-based minerals at high temperatures, it produced a striking, shimmering blue.

The origins of Egyptian blue trace back to ancient Egypt, dating to at least the third millennium B.C.E. It played a crucial role in Egyptian art, appearing in portraiture, architectural decoration, and faience funerary figurines. By the first century B.C.E., the pigment had spread across the Mediterranean, with the Roman architect Vitruvius documenting its production in his treatise De Architectura. Evidence of Egyptian blue has since been found at several Roman sites, including the Baths of Titus and the walls of Pompeii.

A Rare and Exceptional Find

In most cases, traces of Egyptian blue are barely visible to the human eye and require special imaging techniques to detect. At times, the pigment is discovered in fine powders or small fragments. The ingot found in the Domus Aurea, however, is exceptional in both size and condition, suggesting that the pigment was extensively used in the palace’s elaborate frescoes.

The discovery also underscores the expertise of the artisans working on Nero’s imperial residence. Researchers are now investigating whether this particular sample was produced in Italy—potentially in locations like Cuma, Liternum, or Pozzuoli, known centers of pigment production—or if it was imported from Egypt, possibly from Alexandria.

A Connection Between Ancient and Renaissance Art

For centuries, scholars believed the formula for Egyptian blue had been lost following the decline of the Roman Empire, only to be rediscovered in the 19th century by British chemist Humphry Davy. However, recent studies have revealed traces of the pigment in Renaissance masterpieces, including Raphael’s 1512 fresco The Triumph of Galatea and Giovanni Battista Benvenuto’s 1524 painting St. Margaret.

Artists like Raphael and Domenico Ghirlandaio were known to explore the ruins of Nero’s palace for inspiration, marveling at the frescoes that once adorned its walls. The presence of Egyptian blue in these Renaissance works suggests that artists may have unknowingly revived the ancient pigment, further bridging the artistic traditions of antiquity and the Renaissance.

The discovery of this large Egyptian blue ingot within the Domus Aurea is more than just a remarkable archaeological find—it provides a deeper understanding of the sophisticated artistry of the Roman Empire and its enduring influence on later generations of painters.