Ancient, surprisingly well-preserved purple dye uncovered in Greece

Archaeological evidence shows that human love of all things colorful stretches back thousands of years. Color dyes were an important trade commodity in the present day Mediterranean region during the Late Bronze Age. Now, a team of archeologists believe that the Greek island of Aegina was the home of a purple dye workshop. The findings are described in a study published June 12 in the open-access journal PLOS ONE.

The color purple has been associated with royalty and status in many cultures, as purple dye was quite expensive. Understanding the production of these dyes can help archaeologists interpret the culture and trade at the time.

In the new study, a team of researchers from the Paris Lodron University of Salzburg in Austria studied a 5,000 year old Aegina Kolonna in the Saronic Gulf. People in the Middle Bronze Age (about 1,800 BCE) to the early Late Bronze Age lived in large settlements.

“At this time, a densely built-up small town had developed on Cape Kolonna, whose strong fortifications served both fortification and representative purposes,” study co-author and archaeologist Lydia Berger tells Popular Science. “The inhabitants produced many different products, in agriculture and husbandry, but also in handicrafts such as high-quality pottery.”

Kolonna was also well connected in the Aegean trade network. Pottery from these civilizations can be found in many spots in the Aegean world, which comprises the societies that lived around the Aegean Sea in present day Greece.

“The Aeginetans knew how to make use of their favorable location by the sea as a transport route for trade, as protection and as a source of food and raw materials (like purple dye),” says Berger.

The team could tell that a dye workshop was at the site with three main lines of evidence. The first is purple pigment that has been preserved on ceramic fragments. These are likely the remnants of dye containers. According to Berger, the pigments were such high quality that they could still be used to dye clothing today, about 3,600 years later. They also found dyeing tools, including grinding stones and a waste pit at the settlement. Finally, crushed shells of snails whose bodies can be harvested to create these pigments were also at the settlement.

The analysis of the shells and chemical composition of the pigment indicate that the workshop primarily used one species of Mediterranean snail, the banded dye-murex.

“Purple dye is obtained from the glandular secretion of certain sea snails and gives the dyed objects a deep purple, lilac, or dark red color,” says Berger. “A large number of snails and a certain amount of technological knowledge are required for the extraction and production. There is most evidence for the dyeing of textiles, but the color was also used for wall paintings, for example.

The textiles dyed with purple also would have been more valuable because the dyeing process involves more work and materials.

“However, there is no indication in the Bronze Age that purple was a symbol of power and that purple-colored textiles were only reserved for the elite or leaders, as in Roman or Byzantine times,” says Berger.

The excavation here also uncovered many burnt bones from young mammals, primarily lambs and piglets. The team believes that these could be animals that were ritually sacrificed as spiritual offerings to protect the dye site. This practice is known from other cultural sites, but the exact connection between these bones and the dye production is not fully clear.

Future studies could include a comparison of these findings with different eras in the Bronze Age to show how changes in the fishing methods or changes in the snail population due overfishing affected the dyeing and trade process.