The discovery of a Bronze Age dyeing workshop reveals secrets of the most precious pigment in history

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For thousands of years, one color stood out above all others – and was worth more than its worth. weight in goldaccording to an imperial edict from the 4th century.

Tyrian purple was a highly valued pigment, developed in the Bronze Age, and maintained its status into the late medieval period. The ancient Greeks and then the Romans revered the royal color, produced from snails from the Mediterranean Sea, due to its resistance to the inevitable fading of the vegetable dyes used at the time. But with the eventual fall of the Byzantine Empire, the recipe was lost.

During an excavation of two early Mycenaean buildings discovered on the Greek island of Aegina, archaeologists unearthed several potsherds with 3,600-year-old residues of Tyrian purple paint, according to a study published on June 12 in the journal PLOS One.

The pigment is so well preserved that it can still be used to dye textiles today, said the study’s lead author, Dr. Lydia Berger, a senior scientist in the classics department at Paris Lodron University in Salzburg, Austria. The researchers also found crushed mollusk shells and several stone tools, believed to be used in the dye-making process.

The pigment, along with other remains from an ancient purple dye workshop discovered at the ancient site known as Kolonna, has shed some light on the mysteries that still surround the once sought-after color.

A laborious process for an elite color

The oldest record of the production of Tyrian purple dates back to the Middle Bronze Age (2000 BC to 1600 BC), wrote the study authors. Historians believe that the people of the ancient city of Tire, on the coast of what is now Lebanon, were the first to create the dye, which is sometimes called Mycenaean purple. The ancient Greeks called this region Phenicia, or “land of purple”, according to the University of Michigan.

A combination of secrecy surrounding the process and a lack of ancient archaeological evidence from Bronze Age Greek civilizations near the Aegean Sea likely led to the loss of the recipe. It took hundreds of years of research and modern experimentation to come close to the presumed procedure.

“It was a trial and error process, and these people really knew the secret. Now we have lost all the secrets,” said Maria Melo, associate professor in the department of conservation and restoration at Universidade Nova de Lisboa, Portugal, who was not involved in the discovery. “We most likely won’t be able to replicate their process, but we can try to do something similar.”

Creating the historic tone required immense numbers of sea snails found along the coast of the Mediterranean Sea, as documented by ancient Roman authors. Dye craftsmen commonly sought out the species known today as banded dye murex—the species favored by the inhabitants of the island of Aegina, chemical analysis of the pigment found showed—as well as the spiny dye murex and the red-mouthed rocky shell. , according to the study.

Tire purple is often described as a deep reddish purple in ancient Roman times, but depending on the snail used and the amount of heat exposure, the hue can range from a dark indigo to a lilac or deep red, Melo said.

Once collected, the snails had to be kept alive until purple dye makers were ready to crush them and extract the mollusk’s mucous glands. The snail’s remains would then be allowed to leak with regulated exposure to heat for several days, as the color would change from yellow to green and then to purple and sometimes deep red, Berger said.

The process came with a fishy odor, which researchers recognized when they found the purple pigment residue in the recent excavation at Kolonna, she added.

One estimate said it could take more than 12,000 snails to obtain 1 gram of dye. But modern experiments have shown that fewer snails can produce the same amount of dye, depending on how light or dark you want the pigment to be, said Rena Veropoulidou, an archaeologist at the Hellenic Ministry of Culture in Greece who was not involved in the study. new study. For example, Veropoulidou used 800 snails in a 2008 experiment dye five pieces of fabric measuring 20 by 20 centimeters (8 by 8 inches), she said.

Who wore purple?

Who would have worn purple during the Bronze Age remains a mystery, but it is often assumed that the color was only worn by important people due to the intricate dyeing process, Veropoulidou said.

During this period, there is only evidence that Tyrian purple was used in textiles and wall paintings. However, there is more knowledge about the purpose of paint in ancient Rome, where the color was reserved only for the elite and royalty, Veropoulidou explained. There are depictions of Julius Caesar wearing deep purple togas, and during the Byzantine Empire, from 330 to 1453 AD, only the emperor had the right to wear the color.

The newly discovered workshop appears to be smaller, so it’s possible the paint was a private stash used by those who lived on the island, rather than being shipped for trade, Berger added, which could indicate the color was for more common use. . .

“I think the first thing that attracted people’s attention in the first place is that the color is extremely deep – it was a very bright and attractive color – but also the color could be kept bright and pleasant for a long period of time, maybe for two, three, four centuries, which is somewhat surprising if you consider that the way we wash our clothes now, they fade after two or three times of washing them,” said Veropoulidou.

More mysteries behind the hue

During the excavation, researchers also discovered 2,592 mammal remains, including pig and lamb bones.

Although the study authors note that they are unsure of the remains’ connection to the dye-making process, Berger said it could be evidence of religious sacrifices made to protect the site, given the importance of the color.

Another theory is that the bones were used in some way to help regulate the temperature needed to achieve the perfect shade of purple, Melo said. “The knowledge of these people is incredible, because even for us it is difficult to control the temperature (when creating natural dyes). They were able to control temperature to some extent – ​​were these bones there to help control temperature? We do not know.”

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