PURPLE – The range of hues of color occurring between red and blue. In additive light combinations it occurs by mixing the primary colors red and blue in varying proportions. It is a secondary color because two colors (blue and red) make up this color. In subtractive pigments it can be equal to the primary color magenta or be formed by mixing magenta with the colors red or blue, or by mixing just the latter two, in which case a color of low saturation will result. Low saturation will also be caused by adding a certain quantity of the third primary color (green for light or yellow for pigment).
In color theory, a “purple” is defined as any non-spectral color between violet and red (excluding violet and red themselves). The spectral colors violet and indigo are not purples according to color theory but they are purples according to common English usage since they are between red and blue. In art, purple is the color on the color wheel between magenta and violet and its tints and shades. In human color psychology, purple is also associated with royalty and nobility (stemming from classical antiquity when Tyrian purple was only affordable to the elites).
Purple has been used as a dye for textiles for centuries. In ancient times, it was extracted from the Mediterranean sea snail Murex Brandaris. According to Keith Roberts’ book, The Origins of Business, Money, and Markets, around 1200 BC, the Phoenicians discovered that Murex sea snails found in the eastern Mediterranean contained a mucous secretion. Through a process that has been largely lost to time, they managed to turn this black substance into a rich, purplish, powdered dye – Tyrian purple, as it was called by the Greeks. Historians say that it took as many as 12,000 snails to produce fewer than 2 grams of dye. Because of this, it was so expensive that the historian, Theopompus said “Purple for dyes fetched its weight in silver.”
Purple’s elite status stems from the rarity and cost of the dye originally used to produce it. Fabric traders obtained “Tyrian purple,” from the small mollusk that was found only in a region of the Mediterranean Sea near Tyre, a Phoenician trading city located in modern-day Lebanon. Because only wealthy rulers could afford to buy and wear fabrics dyed with this color, it became associated with the imperial classes of Rome, Egypt and Persia.
The symbolization of purple pointed to royalty, nobility and imperialism. In many European societies, the symbolism was even established by law: From ancient Rome to Elizabethan England, “sumptuary laws” forbade anyone except close members of the royal family to wear the color. The expression “born to the purple” rose from this practice, meaning those born into nobility. The color came to represent spirituality and holiness, because the ancient emperors, kings and queens that wore the color were often considered to be gods or descendants of the gods. In ancient mosaics, the Emperor, Justinian I, is depicted dressed in a robe dyed with Tyrian Purple.
Archaeological data from Tyre indicate that the snails were collected in large vats and left to decompose. This produced a hideous stench that was actually mentioned by ancient authors. In his History of Animals, Aristotle describes the shellfish from which Tyrian purple was obtained and the process of extracting the tissue that produced the dye. Pliny the Elder writes about the production of Tyrian purple in his Natural History.
Not much is known about the subsequent steps, and the ancient method for mass-producing the two murex dyes has not yet been successfully reconstructed. The special “blackish clotted blood” color, which was prized above all others, is believed to be achieved by double-dipping the cloth, once in the indigo dye of H. trunculus and once in the purple-red dye of B. brandaris. The dye known as indigo originated from a similar sea snail – Hexaplex trunculus (also known as Murex trunculus or the banded dye-murex) is a medium-sized species of sea snail, a marine gastropod mollusk in the family Muricidae, themurex shells or rock snails. This species of sea snail is important historically because its hypobranchial gland secretes a mucus that the ancient Canaanites/Phoenicians used as a distinctive purple-blue indigo dye. One of the dye’s main chemical ingredients is indigotin, and if left in the sun for a few minutes before becoming fast, its color turns to a blue indigo (like blue jeans).
During his excavation of the ancient Phoenician city-state of Sarepta (1969–1974), located in present-day Lebanon, James B. Pritchard discovered crushed Murex shells and dye-stained pottery containers. It is now believed that these artifacts represent the first production center for Tyrian purple.
The production of Murex purple or “Tyrian Purple” for the Byzantine court came to an abrupt end with the demise of Constantinople in 1204, the critical episode of the Fourth Crusade. In Silk Economics and Cross-Cultural Artistic Interaction: Byzantium, the Muslim World, and the Christian West David Jacoby writes: “no Byzantine emperor nor any Latin ruler in former Byzantine territories could muster the financial resources required for the pursuit of murex purple production. On the other hand, murex fishing and dyeing with genuine purple are attested for Egypt in the tenth to thirteenth centuries.” By contrast, Jacoby finds that there are no mentions of purple fishing or dyeing, nor trade in the colorant in any Western source, even in the Frankish Levant. The European West turned instead to vermilion provided by the insect Kermes vermilio, known as grana, or crimson.
Recently, the archaeological discovery of substantial numbers of Murex shells on Crete suggests that the Minoans may have pioneered the extraction of Imperial purple centuries before the Tyrians. Dating from collocated pottery suggests the dye may have been produced during the Middle Minoan period in the 20th–18th century BC. Accumulations of crushed murex shells from a hut at the site of Coppa Nevigata in southern Italy may indicate production of purple dye there from at least the 18th century BC.
Sources: Jacoby, Silk Economics and Cross-Cultural Artistic Interaction: Byzantium, the Muslim World, and the Christian West – Dumbarton Oaks Papers 58 (2004:197-240) p. 210. Roberts, The Origins of Business, Money, and Markets – (2011) Columbia Business School Publishing. Wikipedia.