The oldest-known synthetic pigment in history, Egyptian Blue was first created more than 5,000 years ago and soon became one of the most sought-after dyes as it adorned tombs, palaces, and statues across Asia, Africa, and Europe.
Parco archeologico del ColosseoA five-pound ingot of Egyptian Blue found at the residence of Emperor Nero in Rome.
More than 5,000 years ago, in ancient Egypt, a mixture of silica, lime, copper, and an alkali was heated, resulting in a bright blue compound known as calcium copper silicate. This striking, vibrant color became the world’s first synthetic pigment, now known as Egyptian Blue.
The Egyptians utilized this pigment extensively, applying it to a variety of materials such as stone, wood, plaster, papyrus, and canvas. It adorned wall paintings, tomb decorations, statues, and numerous artifacts, including cylinder seals, beads, scarabs, inlays, pots, and statuettes. Egyptian Blue became widespread across the ancient world, with massive production centers in Amarna and Memphis, and during the Roman period it was traded extensively throughout the empire.
Then, Egyptian Blue disappeared. After the Roman era came to an end, so too did the widespread production of Egyptian Blue — and the secrets of how to make it were lost for centuries.
However, recent archaeological expeditions have uncovered remarkable bits of Egyptian Blue, most often in mere scraps of powder. But in January 2025, archaeologists announced that they had discovered a massive five-pound ingot of Egyptian Blue during excavations at the Domus Aurea, the imperial residence of Emperor Nero in ancient Rome, revealing to modern eyes just how “incredible” this pigment truly was.
The History Of Egyptian Blue, The World’s Oldest Synthetic Dye
Widely considered to be the world’s first synthetic pigment, Egyptian Blue traces its origins back more than 5,000 years, to roughly 3250 B.C.E. Crafted by heating a mixture of ground limestone, sand, and a copper-containing mineral like azurite or malachite to temperatures between 1470 and 1650 degrees Fahrenheit, Egyptian artisans produced a compound known as calcium copper silicate, a rich blue pigment that was both durable and versatile.
Wikimedia CommonsAn ancient saucer dyed with Egyptian Blue.
Vetruvius, the ancient Roman architect, wrote about the production of Egyptian Blue in Book VII, Chapter 11 of De Arcitectura:
“Blue was first manufactured at Alexandria, and afterwards by Vestorius at Puzzuoli. The method of making it, and the nature of the ingredients, merit our attention. Sand is ground with flower of natron, till the mixture is as fine as flour, to which coarse filings of Cyprian copper are added, so as to make a paste when moistened with water; this is rolled into balls with the hand, and dried. The balls are then put into an earthen vessel, and that is placed in a furnace. Thus the copper and sand heating together by the intensity of the fire, impart to each other their different qualities, and thereby acquire their blue color.”
Unlike other dyes, blue was of particular fascination in the ancient world because of how infrequently this hue appears in nature. Earthly tones like browns and reds, for instance, could be more easily recreated in dyes by utilizing elements from nature. Blue, on the other hand, proved to be more elusive.
Wikimedia CommonsAn Egyptian Blue pyxis imported to Italy from northern Syria, produced around 750 to 700 B.C.E.
Symbolically, meanwhile, blue was deeply important to the ancient Egyptians. Blue symbolized the heavens, the universe, and the life-giving waters of the Nile, representing life, fertility, and rebirth. Thus, the pigment adorned wall paintings, tomb decorations, statues, and artifacts such as cylinder seals, beads, scarabs, inlays, pots, statuettes, and mummy portraits.
Eventually, mass production of Egyptian Blue emerged at various centers across Egypt and later the Mediterranean as a whole. The Roman era further fueled the trade of this blue dye, resulting in the color’s widespread use across the empire.
According to the Getty Museum, Egyptian Blue, despite its rarity, was once a fairly affordable dye. Around 70 C.E., it sold for roughly the same price per pound as the more common red ochre (and half the price of indigo), but by 301, the cost of Egyptian Blue had increased tenfold to around 150 denarii per pound.
For context, a single denarius was essentially a single day’s working wage, meaning that by 301, Egyptian Blue had become far, far less affordable for the average person. Perhaps that is why, at least in part, the production and trade of Egyptian Blue effectively ended after the fall of the Roman Empire.
Over time, as artistic practices evolved and new materials became available, the pigment gradually faded from use and all but disappeared. It wasn’t until the 19th century that scientists began to analyze Egyptian Blue’s chemical components and successfully recreated the pigment, ushering in a resurgence in fascination with the color.
The Rediscovery Of Egyptian Blue And Further Studies Of This Prized Pigment
It was during excavations at Pompeii in the 19th century that researchers rediscovered Egyptian Blue for the first time. There, archaeologists noticed the use of a blue pigment in many wall paintings, and the subsequent discovery of a blue pigment in an artist’s shop in 1814 prompted an analysis of the dye’s composition.
Shortly after, Sir Humphry Davy of the Royal Institution of London concluded that the pigment had its origins in ancient Egypt, and French geologist Ferdinand Fouqué later found that the dye had been created with a copper compound. Since then, the pigment has been the subject of various studies.
Petra Dariz & Thomas SchmidEgyptian Blue pigment balls and a mural fragment unearthed at the ancient Roman cities of Aventicum (top) and Augusta Raurica (bottom).
One 2022 study published in Scientific Reports, for example, utilized Raman microspectroscopy to examine pigment samples of Egyptian Blue recovered from ancient Swiss sites, revealing intricate details about the raw materials and sophisticated techniques employed by Roman artisans.
An earlier study published in Nature Communications in 2020 had also found that the pigment’s exceptional near-infrared luminescence could open new avenues in biomedical research. Researchers found that Egyptian Blue can be exfoliated into nanosheets, which exhibit bright fluorescence under near-infrared light. These nanosheets were significantly brighter than other options currently available for near-infrared imaging studies, making them promising candidates for applications such as bioimaging.
These recent studies made it clear that Egyptian Blue, while beautiful, had a utility beyond pure aesthetics — which is why the discovery of a five-pound ingot of the pigment was found in January 2025, it captured the attention of historians and scholars worldwide.
Excavations At Rome’s Domus Aurea Reveal A Five-Pound Ingot Of Egyptian Blue
Parco archeologico del ColosseoA closer look at the Egyptian Blue ingot found at the Domus Aurea of Nero in Rome.
In a January 20 Facebook post, the Colosseum Archaeological Park announced the discovery of a rare chunk of Egyptian Blue pigment at the massive residence of Nero, generally regarded as one of Rome’s worst emperors.
At the Domus Aurea, archaeologists discovered two sinks that were used, in part at least, to process pigments during the palace’s construction. In or near these sinks, researchers found small jars of various red pigments, an amphora of yellow ochre, and a remarkable ingot of Egyptian Blue. Given that Egyptian Blue was often used to decorate places of wealth and luxury, it is unsurprising that the pigment would be found at Nero’s residence — but the size of the ingot was certainly unexpected.
Parco archeologico del Colosseo The remains of ancient tubs used to process pigments at the Domus Aurea.
“The charm transmitted from the depth of blue of this pigment is incredible,” said Alfonsina Russo, the park’s director. “The Domus Aurea once again excites and returns the brilliance of the colors used by the painters who skillfully decorated the rooms of this precious and sophisticated imperial palace.”
It’s easy to see why researchers have been consistent in their fascination with this ancient synthetic dye. Not only is Egyptian Blue a bold, stunning color, but modern advancements in science have also shown that the pigment could serve a very utilitarian purpose in numerous fields.
Ultimately, it would be safe to say that Egyptian Blue is one of the most significant pigments in human history — one that continues to surprise researchers to this very day.
After learning about Egyptian Blue and its rich history, read about history’s rarest and most expensive dye, Tyrian Purple. Then, discover some ancient Egypt facts that separate myth and truth.
