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For thousands of years, one color rose above all others – and was worth more than its weight in gold, according to an imperial edict from the fourth century.
Tyrian purple was a very valuable color developed in the Bronze Age, and it maintained its status until the end of the Middle Ages. The ancient Greeks and then the Romans revered the royal dye, produced from Mediterranean sea snails, for its resistance to the inevitable fading of the plant-based dyes used at the time. But when the Byzantine Empire eventually fell, the recipe was lost.
During the excavation of two early Mycenaean buildings discovered on the Greek island of Aegina, archaeologists found several pottery fragments with a 3,600-year-old Tyrian purple dye residue, according to a study published June 12 in the journal PLOS One.
The pigment is so well preserved that it could still be used to dye textiles today, said lead study author Dr Lydia Berger, a senior scientist in the Department of Classics at Paris Lodron University, Salzburg in Austria. The researchers also found crushed mollusc shells and various stone tools, which are believed to have been used in the dye-making process.
The dye, along with the other remains of an early functioning purple dyeing workshop discovered at the ancient site, known as Kolonna, has shed some light on the remaining mysteries of the dye. which was very trying.
Labor process for elite color
The earliest record of Tyrian purple production dates to the Middle Bronze Age (2000 BC to 1600 BC), the study authors wrote. Historians believe that the color, sometimes called Mycenaean purple, was first created by people within the ancient city of Bonn, now on the coast of Lebanon. The ancient Greeks called this region Phenicia, or “purple land,” according to the University of Michigan.
The recipe was probably lost due to a combination of secrecy surrounding the process and a lack of early archaeological evidence from Greek Bronze Age civilizations near the Aegean Sea. It took centuries of research as well as modern experimentation to come close to the supposed procedure.
“It was a trial and error process, and these people knew the secret. Now we have lost all the secrets,” said Maria Melo, an associate professor in the conservation and restoration department at Nova University in Lisbon, Portugal, who was not involved in the discovery. “Probably, we won’t be able to reproduce their process, but we can try to do something similar.”
To create the historical pigment, a huge number of sea snails found along the Mediterranean coast, as documented by ancient Roman authors, were needed. Dye artisans were looking for species known today as the banded murex — the favorite species of those on the island of Aegina, chemical analysis of the dye found — as well as the spiny and red mouth rock shell. , according to the study.
Tyrian purple is often described as a deep red purple in the ancient Roman era, but depending on the snail used and the amount of heat exposure, the shade could range from dark indigo to lilac or deep red, said Melo.
Once collected, the snails had to be kept alive until the purple dye makers were ready to press them and remove the mollusk’s mucus glands. The snail remains would then be left to fester with controlled heat exposure for several days, as the color would turn from yellow to green and then to purple and sometimes dark red, Berger said.
The process gave off a fishy smell, which the researchers recognized when they came across the purple pigment residue in the recent dig at Kolonna, she said.
One estimate said it could take up to 12,000 snails to produce 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 the pigment is desired, said Rena Veropoulidou, an archaeologist with the Ministry of Hellenic Culture in Greece. it had something to do with the color. a new study. For example, Veropoulidou used 800 snails in a 2008 experiment to dye five pieces of textile measuring 20 by 20 centimeters (8 by 8 inches), she said.
Who wore purple?
Who would have worn purple during the Bronze Age is still a mystery, but it is often assumed that the color was only worn by dignitaries because of the complex dyeing process, Veropoulidou said.
During this time, there is only evidence of Tyrian purple being used for textiles and wall paintings. However, there is more information regarding the purpose of the color in ancient Rome, where the color was reserved for the elite and royalty only, Veropoulidou explained. There are depictions of Julius Caesar wearing a deep purple togas, and during the Byzantine Empire, AD 330 to 1453, only the emperor had the right to wear the color.
The newly discovered workshop appears to be on the smaller side, so the dye may have been a private stash used by the islanders, rather than being sent out for trade, he said. Berger with it, which may indicate that the color was to be used more commonly. .
“I think the first thing that caught people’s attention, first of all, is that the color is very deep — it was a very vivid, attractive color — but also the color could be kept alive and nice for a long period of time, perhaps. two, three, four hundred years, it’s amazing if you consider that the way we wash our clothes now, after two or three times we wash them,” said Veropoulidou.
More mystery behind the color
During the excavation, 2,592 mammal remains were also discovered, including the bones of a pig and a young lamb.
Although the study’s 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 significance of the dye. .
Another theory is that the bones were somehow used to help with the temperature needed to get the perfect shade of purple, Melo said. “The knowledge these guys have is amazing, because even for us, it’s hard to control temperature (when creating natural dyes). They were able to control the temperature to a certain extent — were these bones there to control the temperature? We don’t know.”
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