History of Purple: A ‘Technological’ Breakthrough
Did you know the purple dye has the most interesting history among all colors, and it was developed by human at last?
From natural dye to affordable synthesized dye that we use today, the dyeing technology of purple transformed through out the centuries. Some of them weren’t very successful, but some were. Understanding why would certainly help us to appreciate the purple clothes that we can feel free to wear today — they did not come easily!
1570 BC: Sea Snails
According to historians, the Phoenicians were the first that discovered purple and used it to dye clothes. The raw material, commonly known as tyrian purple, mostly came from a specific type of sea snail found in the eastern Mediterranean Sea named Bolinus brandaris (i.e. purple dye murex).
The solid color is extracted from this species’ endocrine glands. It would need approximately 10,000 of these sea snails in order to get 1 gram of pigment. The amount of work behind the collection process is unimaginable, thus it was very rare at the time. It was a luxury exclusive to aristocrats and clergy which represented wealth, power, and social position. In Ancient Rome and the Byzantine Empire, for example, only people with royal blood were allowed to wear purple clothing.
Later in 1700 BC, the Phoenicians have began their trade in purple dyed wool and set up a dyeing centre in Tyre (located in Lebanon nowadays) — the term “Tyrian purple” was formed. With the expansion of Greek colonies, this primitive yet practical method continued to spread.
16th Century: Bugs (ew…)
During the Age of Discovery, many European countries voyaged across the ocean to explore other parts of the world. When the Spanish arrived in Central America, they found that the Inca would crush a type of insect called the cochineal (i.e. Dactylopius coccus) and apply their carmine blood on face. These ant-sized bugs live on cacti and rely on cactus juice. The males have wings, but only the females (no wings) have red body fluid. They are pretty lightweight after they are dried — 10o,000 of them only weigh less than a pound.
The Spanish saw the commercial value of these bugs, so they bred a ton of them in Mexico and shipped the dried bugs back to Europe for pigment making — not just dye, but also artist paint and makeup. As a result, the European upper classes loved it. Despite the color does not last long, it has a much higher saturation than Rubia tinctorum (common madder) — an accessible yet unsatisfactory source of natural dye in Europe at the time.
The Spanish made a huge profit from trading cochineal. They kept their reproductive technologies and information of source undisclosed, so only they could produce and sell them (at high prices). The Europeans had no idea where this beautiful pigment came from. Some believed they were flower seeds, while some thought they were fruits. The secret wasn’t revealed until a botanist smuggled out some of these bugs from Mexico.
In many portrait paintings in the 17th century, such as those Dutch Golden Age (like Rembrandt’s) and Baroque paintings, sometimes we can recognize purplish red clothes on the European figures. Now that we know the secret, it isn’t hard to guess where the color came from anymore. If they were rich enough to hire painters, it wouldn’t have been difficult for them to afford and wear expensively dyed clothing.
Before the dried cochineal were imported to the East, China had its own bug named Kerria lacca (see above). They are smaller than ants, commonly found on longan, lychee and sugar-apple trees — harmful for fruits, but great for making powdered cosmetics for cheeks and lips (called rouge or yanzhi in Ancient China). However the pigment extracted from these bugs’ resinous secretion are less vivid than the cochineal, and the colors vary depending on the tree species. Interesting, eh?
It is worth noting that both of these bugs produce more of deep red than purple, just slightly purplish, so people mixed them with indigo blue pigment (have been extracted from plants like Persicaria tinctorial and Indigofera suffruticosa for centuries) to produce a purpler color.
1757: Lichen & Urine (seriously???)
After sea snails, bugs and plants, people were desperate for a cheaper yet effective way of purple pigment making. In 1757, a coppersmith named George Gorden was repairing one of his old boilers in a local dye house in London, UK. He noticed the workers were using several lichens to create purple natural dye, which was very similar to how his grandmother used to produce dye in Scottish Highlands, but somehow this method has’t been popularized and commercialized.
George was inspired. He realized that if he can recreate their process, it would bring a great fortune to him and his family. So when he returned to his home in Leith, he shared his idea with his nephew — Cuthbert Gordon, who happened to be a chemist.
Cuthbert soon found an accessible type of orchil lichen named Roccella tinctoria that was rich in many areas in Scotland. After a series of chemical experiments, he finally worked out an ideal new method with low costs of purple dye making: First he would wash and dry the collected lichens, boil them in salt water and wait for it to get cool, then take a piss in it (a cheap source of ammonia), keep the mixture damp for 3–4 weeks, dry out, grind into powder, and they become a purple dye. Magic!
Once Cuthbert had his very own version of purple dye, he quickly applied for a patent and named it “Cudbear”, similar to his name. He then opened up a factory in Edinburgh to manufacture it. Just like the Spanish, he kept the process secret by building a ten-feet high wall around the facility and made all of his workers swear to secrecy.
However, Cuthbert did not consider the sustainability of lichens, especially in Scotland’s cold climate. The lichen consumption required for the dye’s mass production soon reached 250 tons per year and had to be imported from other countries like Norway and Sweden. His partner in charge of marketing and sales also wasn’t very passionate about this business.
The factory has gone bankrupt. Debt-ridden Cuthbert tried to find a new investor and set up his second factory in Glasgow, but it didn’t work out well either. He had to sell his share to pay off his debt. Unlike Thomas Edison, Cuthbert’s story didn’t end too well.
1856: Synthesized Dye (finally!)
It was the Easter of 1856 — one hundred years after Cuthbert’s discovery. An 18-year-old English student named William Henry Perkin was trying to synthesize some quinine (a medication used to treat malaria) in his lab in London’s Royal College of Chemistry. When he added potassium dichromate (a strong oxidizer) into aniline sulfate salt, some asphalt-like black residue ermeged in the flask. The experiment failed and Perkin was disappointed.
When he tried to clean off the organic residue with alcohol, he accidentally discovered the first synthetic purple dye in human history — mauveine.
Perkin found this purple substance is easily attached to silk and wool, yet does not fade easily, and way more vivid than all previous dyes made from plants, which makes it a perfect new dye. He applied for a patent and it was successfully commercialized because it was during the Industrial Revolution.
Since then, the purple dye is no longer rare and expensive. With new industrial standards, technologically backward printing and dyeing mills were closed and replaced by chemical factories. Delicate craftsmanship was replaced by mechanized mass production. Purple became available to everyone, and it was quickly popularized around the globe.
In the contemporary world, purple is also given new meanings: feminism, LGBTQ, and demonstration. It no longer represents aristocracy and wealth.
