Conny Waters – AncientPages.com – This remarkable painting comes from the second century when Egypt was a Roman province, hence the portraits are more lifelike and less hieroglyphic-like than Egyptian art of previous eras.

Known as “Portrait of a Bearded Man,” the painting contained the purple pigment that came from an Egyptian mummy, but it doesn’t look the same as what you might initially think of as a mummy — not like the golden sarcophagus of Tutankhamen.

Most of these portraits come from a region called Faiyum (some 62 miles southwest of Cairo), and around 1,100 are known to exist.

They’re painted on wood and were wrapped into the linens that held the mummified body. The portraits were meant to express not only the likeness of the person but also give some clues regarding the person’s status.

To know more about this ancient work, researchers analyzed microscopic amounts of purple pigment, no bigger than the diameter of a hair, plucked from this almost 2,000 years old.

“We’re very interested in understanding the meaning and origin of the portraits, and finding ways to connect them and come up with a cultural understanding of why they were even painted in the first place,” says materials scientist Darryl ʙuтт, co-author of the study and dean of the College of Mines and Earth Sciences.

That idea of status is actually very important in this case because the man in the portrait we’re focusing on is wearing purple marks called clavi on his toga.

“Since the purple pigment occurred in the clavi — the purple mark on the toga that in Ancient Rome indicated senatorial or equestrian rank- it was thought that perhaps we were seeing an augmentation of the sitter’s importance in the afterlife,” says Glenn Gates of the Walters Art Museum in Baltimore, where the portrait resides.

Faiyum portraits.

ʙuтт says that the color purple, is viewed as a symbol of death in some cultures and a symbol of life in others. It was ᴀssociated with royalty in ancient times, and still is today.

To make this analysis, the team had only 50 microns in diameter, about the same as a human hair, which made keeping track of it challenging.

“The particle was shipped to me from Baltimore, sandwiched between two glᴀss slides,” ʙuтт says, “and because it had moved approximately a millimeter during transit, it took us two days to find it.” In order to move the particle to a specimen holder, the team used an eyelash with a tiny quanтιтy of adhesive at its tip to make the transfer.

The process of analyzing something like this is a bit like doing surgery on a flea.”

What did they find? To put the results in context, you’ll need to know how dyes and pigments are made.

Pigments and dyes are not the same things. Dyes are the pure coloring agents, and pigments are the combination of dyes, minerals, binders and other components that make up what we might recognize as paint.

Initially, purple dyes came from a gland of a genus of sea snails called Murex. ʙuтт and his colleagues hypothesize that the purple used in this mummy painting is something else — a synthetic purple.

(A) “Portrait of a Bearded Man” (Walters Art Museum #32.6), dated c. 170-180 CE from Roman Imperial Egypt; (B) The portrait under ultraviolet light. The purple clavi on the shoulders appear pink-orange, indicated by an arrow.

With that particle, as small as it was, the researchers could machine even smaller samples using a focused ion beam and analyze those samples for their elemental composition.

The researchers also hypothesize that the synthetic purple could have originally been discovered by accident when red dye and blue indigo dye mixed together. The final color may also be due to the introduction of chromium into the mix.

The analysis suggests that the dye was mixed with clay or a silica material to form a pigment. According to ʙuтт, an accomplished painter himself, pigments made in this way are called lake pigments (derived from the same root word as lacquer). Further, the pigment was mixed with a beeswax binder before finally being painted on linden wood.

The pigment showed evidence suggesting a crystal structure in the pigment. “Lake pigments were thought to be without crystallinity prior to this work,” Gates says. “We now know crystalline domains exist in lake pigments, and these can function to ‘trap’ evidence of the environment during pigment creation.”

The researchers found significant amounts of lead in the pigment as well and connected that finding with observations from a late 1800s British explorer who reported that the vats of dye in Egyptian dyers’ workshops were made of lead.

“Over time, a story or hypothesis emerged,” ʙuтт says, “suggesting that the Egyptian dyers produced red dye in these lead vats.”

And when they were done dyeing at the end of the day, he says, there may have been a sludge that developed inside the vat that was a purplish color.

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