Joy and Poison
Before he became an unlikely American icon, Bob Ross spent two decades in the U.S. Air Force, mostly stationed in Alaska. There, between shifts as a cook and a master sergeant, Ross encountered something unexpected: silence. Snow-covered mountains, mirror-still lakes, and skies that stretched beyond comprehension. He started painting them during his off hours, finding peace in the quiet repetition of nature.
After retiring from the military, Ross vowed never to yell again. Instead, he found his way to a canvas and began speaking in the soft, measured tones that millions would come to recognize. He borrowed and later popularized a technique called "wet-on-wet," which allowed him to complete full landscape paintings in under thirty minutes—live, on camera.
When The Joy of Painting premiered on PBS in 1983, no one expected it to endure. But viewers fell in love with Ross: his calm demeanor, his ferocious perm, and his belief that every mistake was just a “happy little accident.” One color appeared again and again on his palette: Prussian blue. It was the foundation for skies, shadows, oceans, and nightfall. He once said that Prussian blue could “do anything you want it to.”
That wasn’t entirely a metaphor.
Prussian blue—rich, intense, and moody—was the first modern synthetic pigment. Before its discovery, artists relied on ultramarine, which was ground from lapis lazuli and more expensive than gold. Blue, in other words, was a luxury. That all changed around 1706 in Berlin.
A pigment maker named Johann Jacob Diesbach was trying to make a batch of red lake pigment, using cochineal, iron sulfate, and potash. Unbeknownst to him, the potash had been contaminated—likely with animal blood treated with potassium ferrocyanide, which had been used in another experiment in the same lab. When the iron sulfate reacted with the ferrocyanide, it produced something unexpected: a deep, vibrant blue. It was stable, striking, and could be produced at a fraction of the cost of ultramarine.
The color quickly spread across Europe. It appeared in Japanese woodblock prints, adorned military uniforms, and transformed Western painting. Picasso used it during his Blue Period. Hokusai used it to paint his iconic waves. Bob Ross used it to paint serenity.
And its contributions didn’t end there. Prussian blue found utility in places far removed from the canvas. Doctors discovered it could bind to certain heavy metals and radioactive isotopes in the body, allowing them to be safely excreted. It became an essential treatment for thallium and cesium poisoning—so essential, in fact, that it’s now included on the World Health Organization’s list of essential medicines.
It was also used in blueprinting—literally lending its color to the way we designed and built the modern world. And in scientific labs, its chemical structure has been studied for potential use in batteries and data storage.
A beautiful accident. A pigment that saved lives. A color that democratized art and empowered medicine.
But there was a catch.
Prussian blue isn’t toxic on its own—but its structure tells a more complicated story. It’s a tightly bound iron-cyanide complex: Fe₄[Fe(CN)₆]₃. The cyanide ions are held in place by iron atoms, making the compound safe under normal conditions. But the safety is conditional.
When exposed to acidic conditions, such as diluted sulfuric acid, Prussian blue can break down and release hydrogen cyanide—a highly toxic gas once known as “Prussic acid.” This isn’t theoretical. It’s how early chemists first isolated cyanide in the 18th century.
If subjected to high heat, usually around 200°C or above, it decomposes further—releasing cyanogen gas, another dangerous compound. And at even higher temperatures, its breakdown is total, producing iron carbide, nitrogen, and carbon. These reactions don’t happen on a whim—but they demonstrate how closely this beautiful blue sits to the edge of real danger.
Even in simulated stomach acid, trace amounts of cyanide can be released. And yet, paradoxically, it’s still used medically because its stability and benefits outweigh the risks in controlled use.
It’s a pigment that can save lives—or, under the wrong conditions, threaten them. A color that exists on a chemical knife’s edge.
It’s a good metaphor for something else that seems benign—even helpful—until it’s not: debt.
Like Prussian blue, borrowing money can be transformative. It’s how businesses are born, how homes are purchased, how education becomes attainable. Used thoughtfully, debt builds. It enhances. It opens doors.
But the darker side is always there, just beneath the surface. Revolving credit becomes a trap. Interest compounds in silence. What starts as a useful tool becomes an anchor—heavy, invisible, and hard to escape. Financial toxicity isn’t always loud. Often, it creeps in slowly, through small decisions made in the moment, without a full understanding of long-term consequences.
It’s easy to think of debt as either good or bad. But like Prussian blue, it exists on a spectrum. The same compound that paints a masterpiece can, in the wrong context, be fatal. The tool itself isn’t the problem. It’s how you use it. And whether you know what you’re really holding in your hands.
Ross understood this intuitively. The calm wasn’t just a performance—it was a choice. A choice to use the tools of chaos to create peace. That’s the opportunity we all have, in finance and in life: to work with powerful things without letting them overwhelm us.
You can paint with Prussian blue. You just need to know where the edges are.