Arty Farty Friday ~ Merciless Pursuit of Colour

Two interesting articles, about past methods of creating the colours yellow and blue, have lingered in my bookmarks, awaiting a suitable Arty Farty Friday.

The Murky History of the Colour Yellow, by Kelly Grovier. The full piece, available from the link, contains images of relevant paintings, and tells that:
[SNIPS}

Yellow is the cruellest colour. Long before it came to signify cowardice sometime in the middle of the 19th Century (the later insult “yellow-bellied” is from the Jazz age), yellow was the colour most often reached for by Medieval and Renaissance artists when cloaking the callous betrayer, Judas Iscariot, whose duplicitous kiss singled Christ out for the tortures of crucifixion.

If legend is to be believed, some of the most memorable instances of yellow in art history – from the transcendent shimmers of JMW Turner’s lucent landscapes to the troubled music of Vincent van Gogh’s whorling constellations – are caked in cruelty, said to be fashioned from the sickly urine of malnourished cows.

The waste of wasting beasts that had been force-fed nothing other than mango leaves in the Bengalese city of Monghyr was reputedly caught in terracotta pots and clarified to a syrup over an open flame. Believed to be filtered, dried, and clenched into pigment clumps called ‘piuri’ that were then sold to artists, the chalky spheres were crumbled onto the palettes of every artist from Turner to Van Gogh, who in turn smeared their lurid lemony luminescence across the surfaces of their iconic canvases and into cultural consciousness.

All that glistens is not gold

Allegedly born of abuse, surviving vestiges of so-called 'Indian Yellow' glisten with an obscene poignancy from the walls of museums all around the world. When seen in such unsettling light, masterpieces such as Turner’s The Angel Standing in the Sun (1846) and Van Gogh’s The Starry Night (1889) take on a different sheen, appearing to be steeped in the enduring residue of bygone brutality. No longer merely a metaphor for inner unrest, Van Gogh’s whorling stars, painted a month after the artist admitted himself to the Saint-Paul asylum in Saint-Rémy-de-Provence in May 1889, become gritty and real in their aching yellow glister.
...... the process was finally outlawed in Bengal and its use abandoned in Europe....

The second piece:

"The Bible described it as the perfect, pure blue. And then for nearly 2,000 years, everyone forgot what it looked like"
By Noga Tarnopolsky

Forty-nine times the Bible mentions a perfect, pure blue, a color so magnificent and transcendent that it was all but impossible to describe. Yet, for most of the last 2,000 years, nobody has known exactly what “biblical blue” — called tekhelet in Hebrew — actually looked like or how it could be re-created.
At the time of the Second Temple, which towered above Jerusalem until it was destroyed by the Romans, a blue dye of the same name was used to color the fabric used in the clothing of the high priests. Jewish men are still commanded to use a tekhelet-tinted thread in the knotted fringes of their prayer shawls, though what that might look like remained unclear for years....

A possible clue to the ingredients that combined to make tekhelet came from the Talmud, the canonical body of rabbinic texts, in which a man named Abaye asked an elder “this thread of tekhelet, how do you dye it?” He was told that “the blood of the snail and chemicals” (apparently caustic soda or sodium carbonate) had to be boiled together to create the dye. Knowing that the dunes of Dor Beach, a popular spot on Israel’s northern Mediterranean shore, hid ruins of ancient dyeing vats and unexplained mounds of discarded snail shells, the explorers set off in the mid-1980s to identify the species of sea snail they believed might hold the key to finally revealing what tekhelet looked like.

Dor Beach’s Murex trunculus snails seemed promising, but the purplish ink produced by secretions of their glands ended up dyeing cloth yellow. It fell to Otto Elsner, a chemist at the Shenkar College of Engineering and Design near Tel Aviv, to discover that when the ink extracted from the snails was exposed to the sun, it transformed into “deep sky blue.”

Was it, finally, tekhelet? With a blue similar to that of a flawless sapphire, tekhelet was an arresting hue, and everyone seemed satisfied that the mythic color had finally reappeared......

From earliest human history, from the Levant to North Africa, blue has been considered a lucky color. It is still common to see shutters or rooftops painted bright blue as a protective amulet. One legend has it that as the evil eye descends toward Earth, a flash of sky-blue disorients it, sending it away. The superstition reached Europe, and from there the New World. An 1898 compilation of British customs published in the quarterly journal Folk-Lore explains that the “something old” and “something blue” a bride wears “are devices to baffle the Evil Eye,” without which the malevolent forces would “render her barren.”........