“The most favourable season for taking these [shellfish] is after the rising of the Dog-Star, or else before spring; for when they have once discharged their waxy secretion, their juices have no consistency: this, however, is a fact unknown in the dyers’ workshops, although it is a point of primary importance.” – Pliny the Elder,  Natural History (Chapter 62)

Humans have always had a fascination for the rare and unusual, and our ancient ancestors were no different. Nowadays, the questionable purchasing democratization of late-stage capitalism means that anyone can own virtually anything if they can pony up the money to buy it, but in the ancient world, social status as much as wealth often dictated what a person could buy or own. Over time, one of the best examples of this practice became sumptuary laws, that is, laws that restricted the clothing  and consumption of the various strata of society. As we discussed in my entry about the political language of the Prima Porta statue of Augustus, in a world where most of the population was largely illiterate, information was transmitted primarily through visual and symbolic markers. Even more so than today, people relied on the visual cues of a person’s dress to convey their status and place in the social hierarchy. One of earliest written documentations of this practice is from the Greek Locrian code of the 7th century BC, the pertinent law meant restrict (surprise!) the dress of Greek women. The code states that freeborn woman “may not wear gold jewelry or a garment with a purple border, unless she is a courtesan”; though the next line also prohibits citizen men from wearing “a gold-studded ring or a cloak of Milesian fashion unless he is bent upon prostitution or adultery.” As in the early Roman Republic, many of the early Greek city-states generally held excessive luxury as incompatible with a robust polis, and these sorts of laws reflect that.

As the political scene shifted back to stronger monarchical models during the Roman imperial period, sumptuary laws would move toward restricting clothing more strongly by class even within the citizenry, a trend that would survive deep into 17th century. This state of affairs is one of the reasons theater companies of Shakespeare’s time needed an aristocratic patron (e.g., the Lord Admiral’s Men, etc). One of the most important ways a noble patron financed productions was giving his actors old clothes to use for costumes made of materials they literally could not buy themselves, even if the company had possessed the funds. Sumptuary laws restricted clothing by materials (e.g., only certain classes could wear silk or various furs), but also certain colors were prohibited to those outside of the ruling class. Arguably the most famous of these was murex, or royal purple, which was among the mostly costly and labor-intensive dyes of the ancient world. So I thought we’d take a look into its history and how one color so profoundly shaped ancient society.

This dye, the original color purple, went by many names. Our English name for it comes from the Greek porphúra (πορφύρα) and by extension, the Latin gloss of the Greek, purpura. During its increasing monopolization by kings and emperors, it would eventually gain its specific designation of “royal purple” or “imperial purple.” But in its most ancient roots, the color was more readily identified by its source, murex (a sea snail), and its producers, the seafaring Phoenicians. Although there is some evidence that the ancient Minoans of Crete (c. 3500-1100 BC) may have pioneered the dye, murex was commonly called Phoenician or Tyrian purple, the ancient Phoenician city of Tyre being believed to be the original source of the purple dye. Tyre, now in modern Lebanon, is one of the oldest continuously inhabited cities in the world, and its founders, the Phoenicians, were an ancient Semitic people who settled on the Lebanese coast as early as 2900 BC, according to both ancient sources like Herodotus and the archeological record. Indeed, the Greek word “Phoenician” (phoînix; φοῖνιξ) is simply a cognate of porphúra, demonstrating how intertwined the Phoenicians were with this dye.

In Greek mythology, the progenitor of the Tyrian Phoenicians was Phoenix, one of brothers of Europa. When Zeus as a bull abducts Europa, Phoenix, along with his other brothers, Cadmus and Cilix, are sent by their father after her, with orders not return until they are successful. They never find her (Zeus takes Europa to Crete, where she is the first queen of the island, which maybe is the mythological connection between the Minoans and Tyrian murex), so the brothers settle down and form their own kingdoms. Cilix becomes the eponymous first king of Cilicia, Cadmus founds Boeotian Thebes, and Phoenix founds the city of Tyre. Supposedly during his reign, the philosopher Heracles of Tyre is walking his dog on the beach when the dog chews on some sea snails that have washed up on the shore, which stain the dog’s mouth purple and leads to the dye’s discovery. The Byzantine chronicler John Malalas (c. 491-578 AD) claims in his Chronographia that subsequently Phoenix was the first monarch to wear murex and proscribe its use (II:9), though as we’ve already seen, he would hardly be the last.

As early as the second millennium BC, the Tyrian Phoenicians had turned the manufacture of murex into a proto-industrial process and had established a monopoly over its production and trade. Many ancient sources groused sourly over the Phoenicians’ infamous control over their proprietary manufacturing process of the dye, which means some of it is only our historical conjecture (there are some really fun YouTube videos of people attempting to replicate the dye DYI). But the Phoenicians knew the value of their trademark product. Aside from its vibrant, rare color, murex was famous for its lightfastness, meaning it was strongly resistant to fading—an especially unusual property for natural dyes. In fact, it was widely held that murex-dyed clothing actually deepened in color over time, giving an already prized garment a visible pedigree of ownership. Importantly, murex was also known to be largely colorfast, which permitted it to be washed without loosing its tone or running.

So what about dye material itself? Well, murex comes from the mucus secretions of several interrelated predatory sea snails of the Muricidae family, namely Bolinus brandaris, Hexaplex trunculus, Stramonita haemastoma, and a few other smaller sub-species. These species are still commonly known by names such as dye murex or purple-dye murex and are indigenous to the eastern Mediterranean, as well as the Atlantic coast of Morocco. This second western pocket of murex-producing snails likely explains the Phoenician colonization of ancient Carthage and Iol in Mauretania on the north African coast, to provide a closer base of trade operations for the dyers working on the far-flung Moroccan production sites that would continue to be known as the Purple Islands well into the Roman period. The snails produce the mucus from a gland under their mantle (the outer layer of their bodies that creates their shells, if they have one) and use the secretion in the wild to sedate prey and as a defensive mechanism, as well as a lining to protect egg sacs because it is mildly antimicrobial.

The dye material can be extracted in one of two ways. Either the snail’s hypobranchial gland can be, for lack of a better description, “milked” to obtain the mucus, or the snail can be simply crushed up. The “milking” is a less-destructive, renewable way to make the dye, but it is far more labor-intensive, even if it essentially entails poking the snail until it angrily produces the necessary mucus. The dye can also be harvested by removing the hypobranchial gland, but this is equally time-consuming, not to mention it involves an advanced knowledge of mollusk biology. And there’s the fact that sea snails are small. It has been estimated that to make less than 2g of pure murex, enough to dye the single line of purple trim on a Roman magistrate’s toga praetexta, one would require as many as 12,000 snails. Indeed, the Greek geographer Strabo wrote of hating his visit to Tyre because the smell of that much seafood processing was exactly what you’d imagine. You also needed all of those snails now, because, like most natural dyes, ingredient freshness is a key component of achieving the highest quality colors. The Phoenicians literally had to build murex factories on the far side of Africa for their Purple Island operations because the dye would suffer if the mollusks were sitting on a ship even the distance between western Morocco and western Algeria. One begins understand why murex-dyed garments commanded the exorbitant prices they did. The Greek historian Theopompus reports that in the 4th century BC, pure murex was literally worth its weight in silver.

Even once the murex was obtained from the snails, the dye production process would take at least several days to achieve the specifically desired color and intensity, which like most ancient artisanal products, involved a sophisticated, likely largely oral, tradition passed from master dyers to their apprentices and successors. Despite the tight lips of the Phoenicians, the Roman historian Pliny the Elder provides a plausible recipe for a version of the process in his Natural History: “After it [the snail] is taken, the vein [the hypobranchial gland] is extracted…to which it is requisite to add salt, a sextarius [~20 fl. oz.] to every hundred pounds of juice. It is sufficient to leave them to steep for a period of three days, and no more, for the fresher they are, the greater virtue there is in the liquor. It is then set to boil in vessels of tin, and every hundred amphorae ought to be boiled down to five hundred pounds of dye, by the application of a moderate heat; for which purpose the vessel is placed at the end of a long funnel, which communicates with the furnace; while thus boiling, the liquor is skimmed from time to time, and with it the flesh, which necessarily adheres to the veins. About the tenth day, generally, the whole contents of the cauldron are in a liquefied state, upon which a fleece, from which the grease has been cleansed, is plunged into it by way of making trial; but until such time as the colour is found to satisfy the wishes of those preparing it, the liquor is still kept on the boil. The tint that inclines to red is looked upon as inferior to that which is of a blackish hue. The wool is left to lie in soak for five hours, and then, after carding it, it is thrown in again, until it has fully imbibed the colour.” (Chapter 62: The Natural History of Fishes).

As Pliny alludes to, there were also several different murex shades, denoting different chemical/enzymatic compounds present in the snails and by extension, the perceived quality of dye. For much of the Roman republican era into the early imperial period, when a Roman source calls something “purple,” the color they might be actually describing is more of a reddish violet, which you can see in topmost fabric bolt shown in the picture below. But as the middle bolt shows, the murex snails were more than capable of producing a much truer purple, as well as a bright scarlet, as shown in the third bolt.

As one might suspect if one remembers the complimentary color wheel, murex snails were also able to produce a much more blue-colored dye, often referred to as “royal blue” or “hyacinth purple.” This came from a related, but possibly separate, mollusk species in these regions and is thought to have been a special product of the Moroccan Purple Islands, where those snails were more common. It is possible this blue version of the dye is related to the Hebrew dye tekhelet (תְּכֵלֶת). Tekhelet was a blue-violet dye used as a secular royal color and as a sacred color proscribed for the fringes (tzitzit; צִיצִית) of prayer shawls (talit; טַלִּית) and priestly garments since the Exodus period. The dye’s origins were gradually lost over the medieval diaspora, but the general confusion of how to make the dye seems to stem from the era around the destruction of the Second Temple by the Romans in the first century AD. This has led to a compelling theory that tekhelet might have shared a source with the murex-adjacent royal blue mollusks, as Nero had made it illegal for anyone but the emperor to wear blue and the Talmud recounts that a group of rabbis in the Tractate Sanhedrin were caught by the authorities trying to smuggle tekhelet against regulations around this time.

As evidenced by Nero’s decrees, the Romans were as fond murex as the Phoenicians and the Greeks had been before them. Through the Roman Republic and the Empire, as previously mentioned, murex was used to create both the broad purple stripe of the toga praetexta and the thin purple stripe of the togas of men of eques rank (the trabea—though later this label would be co-opted more generally into consular dress). More exotic of course was the toga picta, the solid purple toga of a Roman general celebrating an official triumph. As time went on, in part as a legacy of Caesar’s dispensation to himself to continually wear his toga picta, murex increasingly became the dye reserved for the leader(s) of Rome. Octavius restricted its use to the “governing class,” which allowed senators to continue their hereditary use of it on the toga praetexta, but by the 4th century AD, imperial sumptuary laws had contracted so much that murex was solely the domain of the emperor and his family. This is the era, and the following early medieval period, from where we get the idioms where “purple” is used as a metonym for the imperial throne. To “don the purple” was to ascend to the office of emperor, and to be “born in the purple” was to denote a person as the progeny of a reigning emperor. In fact, by the 9th century, Porphyrogénnētos/Porphyrogénnētē (literally “purple-born”) would be an official title given to the emperor’s children.

The shift of the center of the empire to Constantinople would seem to only accelerate the imperial love affair with murex and the Byzantine emperors devoted an enormous amount of resources to running the murex industry to ensure a steady supply of the dye for their personal use. Production would continue on this monumental scale until 1204, when the western European armies of the Fourth Crusade forgot about fighting the infidels of Syria and instead ransacked Constantinople, marking the end of the unified Byzantine Empire and the Eastern Holy Roman Empire. After the fall of Constantinople, murex would continued to be used at least through the end of the 13th century in Egypt, but on a much more domestic scale and never at the level of production seen in the prior millennium. Latin Europe, even among the Frankish kingdoms of the Levant, would largely abandon the labor and expense of murex for the slightly easier-to-acquire vermilion, made of either the Kermes vermilio insect, or cinnabar (mercury-sulphide).

In hindsight, it’s amazing, given the process and the ancient world’s appetite for this dye, that humanity didn’t manage drive the murex snails into extinction by the modern era. But maybe the diminishing of the Byzantine emperors (and their mammoth consumption of murex) through the destruction of European Constantinople is one of the few positive end results of the otherwise ridiculously catastrophic Fourth Crusade. Proving once again that humanity usually only manages to be environmentally-conscious by accident when we are distracted by own stupidity with each other to turn our full force on our surroundings.