rove of ancient Murex trunculus snail shells were recently excavated at the Tel Shikmona site in northern Israel, dating back to the 10th-7th centuries BCE. Being organic material, one of the Timna cloth pieces was also sent for radiocarbon 14 testing at a laboratory in Oxford, where the date of 1,000 BCE was calculated.
During the early Iron Age, “We already knew that there was a true purple textile dye industry,” she said, but until now, there had been no dyed textiles. According to the paper, the first archaeological evidence for use of the dye dates from the 19th century BCE in the form of murex shells.
“I’m so happy that Erez [Ben-Yosef] gave us the opportunity to peek into the clothes closet from the period of David and Solomon and see the wardrobe of the elite that lived in the period at the copper mines,” she said.
“I suppose that if we were to peek into David and Solomon’s closet we’d see similar clothing — and perhaps even more true purple,” said Sukenik.
Getting hands dirty for science
Discovering that the 3,000-year-old textile scraps were dyed with royal purple was only one step of the journey undertaken by this ambitious research project. Another chapter not recorded in the PLOS One paper saw Bar Ilan University Prof. Zohar Amar visit the fish markets of Italy to conduct experiments on the three species of snail.
The three species of snail are endangered in Israel and Amar told The Times of Israel that he couldn’t obtain enough samples to truly conduct his experiments. So he took himself to Milano, which holds the largest fish market in Europe. There, the snails are eaten as part of the varied Italian diet and two of the species — Spiny Dye-Murex (Murex brandaris) and Banded Dye-Murex (Murex trunculus) — are plentifully traded in the market.
Amar rented a laboratory and hired local staff to conduct hundreds of experiments on thousands of snails. Each snail’s dye gland, he said, only holds a minuscule amount — circa one gram. So he ordered a massive supply, which arrived in special refrigerators that kept the snails fresh and alive.
Even in ancient texts such as the writings of the Roman author Pliny the Elder and the Jewish Talmud, it was emphasized that the snail glands be procured fresh, which creates the best dye. Amar said, having used dried glands that were shipped to Israel in some experiments, he can now vouch for the value of fresh specimens.
The glands were traditionally dried in the sun, but Amar imported an oven from Israel to speed up the process.
“It was very hard work, very stinky,” he said, much like working in a fresh fish market, he said.
The Italian fishermen who delivered the snails “thought I was a bit crazy. What they ate, I threw away, and what they threw away I used,” he laughed.
Two thousand years ago, the rabbis discussed how impure creatures such as the sea snails — forbidden from an observant Jewish diet — could be the source of a dye used in such sacred spaces as the Tabernacle and Temple.
Amar answered that through his experimentation with the snails, he realized that nothing of the meat of the snail remains. Through the chemical processing of the snail glands into dye, “the material turns into something else.”
While two of the species were in plentiful supply, locating the third species saw Amar take out the big guns — his Italian mother in law. With her help, the third species, Red-Mouthed Rock-shell (Murex haemastoma), was sourced in Palermo, Sicily. He traveled to the Mediterranean’s largest island, only to be disappointed when inclement weather caused the fisherman to come back without a catch. Only after a subsequent trip could he successfully harvest the third snail’s dye glands.
Although Amar had studied the theory behind the preparation of the true purple and associated azure dyes, “in conducting in the practical work I learned a lot about the historical sources. It was like time tunnel to the past,” he said.
He conducted his initial experiments bare-handed, only to discover that the dye that lasts millennia on archaeological artifacts quickly stained his hands blue for