This dark, impious colour garners its characteristics from the very onset of its mistaken creation, which depends on two people: Johann Konrad Dippel, “ein indifferentistischer Schwarmer” (“an indifferent fanatic”) who in the early 1700s had begun vehemently mocking Lutheran Christianity, and Johann Jacob Diesbach, a dye maker who was probably less-interesting a person than Dippel, who mistakenly killed a man in a duel. A duel. Atheists were more proactive in terms of their beliefs in the 1700s, apparently.

Having read the writings of Spanish mystic Ramon Llull, Dippel became sure of his ability to transmutate lead into gold. Alchemy was all the rage, as inter-imperial currency and trading relied still on actual gold. Dippel moved to Berlin in the first few years of the 1700s to escape creditors - so we can assume his optimism about his abilities in the transmutation of lead into gold, were flawed. In Berlin, he sought to develop a “universal remedy,” which Dippel claimed could cure fevers, colds and epilepsy. Again with that abundant optimism...

In 1706, Diesbach, who shared Dippel’s laboratory, was stewing a deep red pigment cochineal lake, created by boiling insects, and the addition of alum (hydrated potassium aluminum sulfate), green vitriol (iron sulfate), and potash (mined salts containing potassium). Diesbach was fresh out of mined salts containing potassium, so he lent some from Dippel, and while emulsifying the chemicals with the boiled insects, he saw that he’d got the purity wrong and created not deep red, but Prussian Blue.

The mistaken colour had arisen because the potash had been used prior, and was contaminated with animal blood, which when mixed with the green vitriol, the blood caused a reaction, and a blue so beautiful. Prussian Blue was the world’s first synthesized colour pigment. Before, blue was a difficult colour to use create and work with: Azure blue turned green upon contact with water; Indigo was neither colourfast; Ultramarine could be made only from crushed Lapis Lazuli mined in the Badakhshan mountains in Afghanistan and cost more than gold - Renaissance artists had to negotiate with their patrons for individual drops of blue upon receiving a commission.

The oldest known use of Prussian Blue was in 1709, seen in Mary Magdalene’s veil in Pieter van der Werff’s Entombment of Christ, housed in the painting gallery at Park Sanssouci in Potsdam, the royal house of the former Prussian Empire. Van der Werff was one of the court painters of the Prussian House, where he and the other painters were closely connected to the Royal Academy of Arts in Berlin, which shared a room with the Royal Academy of Sciences, which is where the pigment was synthesised, likely in 1706. When the pigment began to be promoted to artists elsewhere, it also became known as Berlinisch Blau (Berlin Blue). Not long after the colour garnered attention artistically, Frederick the Great began using it on the Prussian Army’s uniforms, which is fitting for a colour made from Iron & Blood. After the Prussian Army’s intervention at the Battle of Waterloo, “my Prussian blue” became a term of endearment in England. The Impressionist artists fell in love with the colour, while only Renoir declared that he was “horrified” by the colour. Perhaps due to its synthesis, or his indifference. 

And that is how I caught Cézanne off guard, coming along bent over in thought. His face like a potter’s, sun-burned, looked startled as the shadow of nearby leaves played over it. He had a small, bony head with rosy skin, lively eyes, and a white mustache carelessly smeared with prussian blue.

— Jules Borély, Conversations with Cézanne

Today, Prussian Blue found its way to wheres other than the artistic. It is used to remove certain radioactive materials and heavy metal poisons from bodies. Prussian Blue is also used to test for Cyanide, where Iron Sulfate is added to a solution suspected of containing cyanide: the formation of Prussian Blue is a positive test. Thus, the Leuchter Report, a document supporting the denial of The Holocaust, cites the lack of Prussian Blue on the walls of the Hydrogen cyanide gas chambers at Auschwitz as proof that the chambers could not have functioned as such. (In response to the claim, the amount of Hydrogen cyanide required to kill a person is so minuscule that traces are not necessarily left in a magnitude enough to show Prussian Blue in the above test).

In 2012, Prussian Blue made its way into the Spring/Summer Prada collection, and it began showing up many places elsewhere thereafter, too. In response to the trend, buyers for department stores unaware of the actual colour, carelessly assumed they were seeing Teal and filled their stores’ rails with the incorrect colour.

Find the colour wheel to the end of this article, which distinguishes the colour, clockwise, starting with Prussian Blue, Prussian Green, Teal, Palatinate Blue, similar to International Klein Blue, Ultramarine, Royal Blue, Navy Blue.

Inspiration:

A walk around Park Sanssouci in Potsdam
Jens Bartoll of the Prussian Palaces and Gardens Foundation, “The Early Use of Prussian Blue in Paintings”
Joshua Cohen, “Thirty Six Shades of Prussian Blue”
George Pendle, “Colors / Prussian Blue”

Indebted to Stiaan Louw especially, for the marvelous outfit he produced on request.