Science reveals secrets of mummy portraits

How much information can you get from a speck of purple pigment, drawn from a nearly 2000 year old Egyptian portrait, not larger than the diameter of the hair? Plenty, according to a new study. An analysis of that spec can teach us a little bit about how the pigment was made, what was made of it, and who made it. The study is published International Journal of Ceramic Engineering and Science.

“We are very interested in understanding the meaning and origin of portraits and finding ways to connect them and a cultural understanding of why they are drawn in the first place,” says Daniel Butt, co-scientist. Study and Dean of Mining and Earth Sciences.

Faim mummies

The purple pigmented portrait came from an Egyptian mummy, but it won’t look like what you initially thought as a mom – not like Tutankhamen’s golden sarcophagus, or the side-by-side paintings on the murals. Papaya. Not even like Boris Carloff.

Called the “Portrait of the Dardard Man”, the portrait dates from the second century when Egypt was a Roman province, so the paintings are more vivid and less hieroglyphic than the art of earlier Egypt. Most of these portraits come from a region called Faim, and about 1,100 are believed to have survived. They are painted on wood and wrapped in linen that has a mummified body. These portraits were meant to express the similarities of the person, but also their status – real or ambitious.

That idea of ​​position is really very important in this case because the man we are focusing on the portrait wears purple marks. Clevie On his toga. “Since the purple pigment ClevieGlenn Gates of the Waters Art Museum in Baltimore, where the portrait resides, says Glenn Gates of the Waters Art Museum in Baltimore, where a purple sign was shown on a toga in ancient Rome, indicating that in ancient Rome there was a sanatorium or equestrian. .

Butt says the color purple is seen as a symbol of death in some cultures and a symbol of life in others. It was associated with royalty in ancient times, and still is today. Butt, concluding author Victoria Finale, says that purple, located at the end of the visible color spectrum, could indicate the end of the known and the beginning of the unknown.

“So the presence of the purple on this particular portrait made us wonder what it was made of and what it means,” says Butt. “The color purple raises a lot of questions.”

Lake pigments

Through a microscope, Gates observed that the pigment looked like crushed gemstones, containing particles ten to a hundred times larger than typical paint particles. To answer the question of how it was made, Gates sent a particle of pigment to Butt and his team for analysis. The particle was only 50 microns in diameter, as much as human hair, making its track challenging.

Butt says, “The particle was sent to me from Baltimore, sandwiched between two glass slides, and since it moved about a millimeter during the transition, it took us two days to find it.” To move the particles on the particle holder, the team used an eyeliner using a small amount of adhesive on its tip to transfer. “Analysis like this is like having surgery on a flea.”

With that particle, as small as it was, researchers would be able to machine even small samples using a concentrated ion beam and analyze those samples for their original composition.

What did they get? To put the results in context, you need to know how colors and pigments are made.

Pigments and colors are not the same thing. Colors are pure coloring agents, and pigments are a combination of dyes, minerals, binders, and other ingredients that make up what we can identify as paints.

Initially, the purple colors come from the glands of the sea snail genus Murex. Butt and his colleagues speculate that the purple used in this mummy painting is something else – an artificial purple.

Researchers have also speculated that the origin of the artificial purple would have been discovered by accident when red and blue indigo dyes were mixed together. The final color may also be due to the introduction of chromium into the mixture.

From there, the mineralogy of the pigment sample suggests that the pigment was mixed with clay or silica material for coloring. Butt, according to a skilled painter himself, the pigments made in this way are called lake pigments (derived from the same root word as Rogan). The pigment was mixed with a wax wax binder before it was finally painted on linden wood.

The pigment showed evidence indicating the crystalline formation in the pigment. “Before this work, lake pigments were considered without crystallinity,” says Gates.

Below the barrel, air, watt

Another detail adds a little more depth to the story of how this portrait was created. Researchers found significant amounts of lead in the pigment and connected it with the observations of a British researcher in the late 1800s who reported that colored vats were made from lead in Egyptian dior workshops.

“Over time, a story or hypothesis emerged,” Butt says, “suggesting that the Egyptian diorama painted red in these lead watts.” And when they were painted at the end of the day, he says, there may have been a mud that developed inside the pot that was purple in color. “Or, they were very smart and they must have found a way to take the color red, move the color towards purple by adding salt with transition metals and mordant. [a substance that fixes a dye] To intentionally synthesize purple pigment. We don’t know “

Extensive effects

These buttons are not the first time using scientific methods to learn about ancient artwork. He has been involved in similar investigations in the past and has drawn on his research and artistic background to develop a class called “Art Science” which includes studies and discussions on topics involving dating, understanding and various historical artifacts of opposite engineering. Leading newspapers for ancient art.

He says, “Mixing science and art together is just entertainment. It’s a great way to make learning more accessible to science.”

And there are also broader effects of work. Relatively little is known about mom portraits, including whether multiple paintings were made by the same artist. Analyzing pigments at the atomic level can provide the chemical fingerprint needed to link portraits to each other.

“Our results suggest a tool for documenting the similarity of the time and place of construction of the mummy paintings as most were confessions and lacked archaeological context,” says Gates.

“So we can connect families,” Butt adds. “We will be able to connect artists to each other.”