Unearthing Bronze Age Dye Workshop Sheds Light on Historic Pigment

For millennia, one color stood out above all others and was considered so precious that it was literally valued more than gold. This is according to an imperial edict from the fourth century. The color in question? Tyrian purple. 
 
Tyrian purple was a highly prized pigment developed during the Bronze Age that managed to hold onto its elite status well into the late medieval period. Such esteem for this particular hue came from both ancient Greeks and Romans, who revered it for its durability compared to plant-based dyes commonly used at the time, which would inevitably fade with age. However, following the fall of the Byzantine Empire, the secret recipe for creating Tyrian purple mysteriously vanished. 
 
Recently, though, archaeologists excavating two early Mycenaean buildings on Aegina, a Greek island, stumbled upon pottery fragments containing residue of this 3,600-year-old dye. According to a study published in PLOS One on June 12th, not only has this pigment survived thousands of years remarkably intact, it could even be utilized today to dye textiles! 
 
Dr. Lydia Berger, a senior scientist in Paris Lodron University's department of classics based in Salzburg, Austria, affirms that alongside these remnants, they also discovered crushed shells from mollusks and various stone tools believed to have been used during the production process. 
 
The discovery at Kolonna provides invaluable insights into how this once-coveted shade might've been manufactured during antiquity. 
 
Historians believe people residing within what is now Lebanon first created Tyrian purple around the Middle Bronze Age (2000 BC–1600 BC). This region, known by the ancient Greeks as Phoenicia, or "land of purple,"  suggests where such a name originated, according to Maria Melo, an associate professor at Nova University Lisbon, Portugal, who wasn't involved with recent findings but provided commentary nonetheless. 
 
Melo explains that the combination of secrecy surrounding production coupled with a with a lack archaeological evidence found near the Aegean Sea likely contributed to the to the loss of the original formula over centuries. Even with modern scientific techniques and extensive research, it has been challenging to recreate the exact processes ancient civilizations must've used. 
 
Creating Tyrian purple wasn't an easy task; it required thousands of specific sea snails indigenous to the to the Mediterranean coastline. These species included banded dye-murex (most favored by inhabitants of Aegina), spiny dye-murex, and red-mouthed rock shell, as per study findings. 
 
The color spectrum of Tyrian purple could vary greatly depending on which type of snail was used in the creation process and how much heat exposure occurred during processing. It could range from deep indigo to a lighter lilac or even a deep red shade, says Melo. 
 
In order for extraction to occur, these mollusks had to be kept alive until they were ready for crushing, whereupon their mucus glands would then extract the pigment necessary to create dye, explains the Berger lead author study, adding that this entire ordeal often resulted in a in a rather unpleasant fishy odor, which researchers recognized when they discovered preserved residue at the Kolonna site. 
 
Estimates suggest around 12,000 snails were needed to produce just one gram of this unique pigment, although more recent experiments have shown fewer can yield the same results depending on the on the desired intensity of color, according to Rena Veropoulidou, an archaeologist at the Hellenic Ministry of Culture Greece, who also provided commentary despite not being directly involved in the new findings. 
 
Those who wore garments dyed using Tyrian purple are believed to have been individuals of high social standing due to the complicated nature involved in producing such a vibrant color, suggests Veropoulidou. During the Bronze Age, there's only evidence of textile wall paintings having utilized dye; however, its use became far more exclusive over time, especially among Roman elite royalty alone, who permitted wearing garb-adorned hues, she further explained, pointing out depictions of Julius Caesar donning deep purple togas. Byzantine emperors later followed suit between AD 330 and 1453. 
  
Interestingly, the recently discovered workshop appears quite small, leading some to speculate that perhaps the product created here might've served as a as a private stash rather than intended for general trade, says Berger, suggesting that maybe color wasn't quite as exclusive as once thought. 
 
Veropoulidou adds, "I think the first thing that attracted people's attention, first of all, is that the color is extremely deep—it was a very vivid, attractive color—but also that the color could be kept alive and nice for a long period of time, maybe for two, three, or four centuries." 
 
During the excavation process, researchers also unearthed 2.592 mammal remains, including bones, young pigs, lambs, and connections. The dye-making connection is still unclear, but Berger speculates these might've been part of religious sacrifices aimed at protecting the site given its importance, while Melo suggests they could've had a role helping regulate temperature needed to achieve the perfect shade of purple, adding, "It's amazing knowledge, these guys, because even us it's difficult to control temperature (when creating natural dyes). They were able to control temperature at certain degree. We don't know."