The Story of Blue

Sonne au comble de l'or
l'azur du jeune hiv
er
– Paul Valéry

For me, blue is air, wind, melancholy. It is like a Fellini film—always haunted by the whisper of the wind, the scent of things, and the fleeting moments of time we wish we could hold in an eternal present. Blue can carry regret; it is, in a way, a conservative principle. Blue has always held a strange duality: so immediate, yet once so elusive. Looking back to antiquity, it fascinates me that Homer never described the sea as blue, but as ‘wine-dark.’ In Greek, kyaneos evoked a dark, mineral depth, while glaukos hovered between gray, green, and blue. The Romans spoke of caeruleus, tied to the sky (caelum), and of lividus, the bruised, bluish tone of flesh. They never elevated blue; it was the color of outsiders, the hue of Celts painted in woad. Only the Egyptians seemed to truly revere it. They invented Egyptian blue, the first artificial pigment, and made it the shade of eternity and the divine.

In the Middle Ages, blue nearly vanished from prominence. Christian art turned to red, white, and black, leaving blue to the margins. Yet the word itself was evolving. The Germanic blāo—and its Vulgar Latin adoption, blavus—once meant something far less precise: shimmering, lustrous, dark, gray, even pale or yellowish. That ambiguity makes me realize how fluid color once was, before language fixed its boundaries. From blāo we inherited English blue and French bleu. Meanwhile, through Arabic lazaward came the words azure, azzurro, and azul, all born from lapis lazuli.

Then, in the 12th century, blue was transformed. Artists began clothing the Virgin Mary in ultramarine, ground from lapis lazuli more costly than gold. What had been humble became heavenly. Heraldry embraced azure as one of its noble tinctures, and kings like Louis IX made blue their emblem. A forgotten hue became a sacred, regal presence.

By the Renaissance, ultramarine shone as a color of prestige, truth, and constancy. Painters reserved it for the highest subjects, poets linked it to loyalty, and explorers carried its name across the seas as azul. Blue had finally claimed its place.

The modern era democratized it. Prussian blue appeared in 1704, followed by cobalt, cerulean, and synthetic ultramarine. Blue poured into uniforms, flags, and revolutions; it became the shade of liberty, of nations, of collective identity. Goethe called it spiritual, a color that retreats yet draws the soul inward.

In the 20th century, painters gave blue an entirely new destiny. The Expressionists used blue to conjure emotion, depth, and inner turbulence—think of Kandinsky, who saw blue as moving ‘toward the infinite,’ or Franz Marc, who painted blue animals to symbolize spirituality and hope. Even Van Gogh’s Starry Night swirls with blue, capturing both wonder and melancholy. Later, Picasso entered his Blue Period, transmuting sorrow into tone. Yves Klein went further still, reducing blue to its purest intensity with his International Klein Blue, turning it into an immaterial field of experience. For Klein, blue was not simply a color but ‘the most abstract color of all,’ a space in which one could lose oneself.

Today, I see blue everywhere. In the jeans that became the fabric of daily life. In corporate logos designed to inspire trust. In flags that mark belonging. Blue is calm, yet melancholy; humble, yet exalted. Once overlooked, it is now the world’s favorite color.

Blue is more than a hue. It is an idea shaped across centuries—etymologically born of caelum, blāo, and blavus; symbolically stretched between heaven and earth; culturally tied to faith, power, and identity. Its story mirrors our own: restless, mutable, and ever searching for meaning.

I’ll end with a little story from my own family. After World War II, my paternal grandfather, a house painter, bought a massive surplus of blue paint from the military. He had so much of it that whenever a client asked how he planned to paint their home, his answer was always the same, year after year: “All in blue, yes, all in blue…” (in our dialect, tutt’azzurr, tutt’azzurr).

That simple phrase stuck. Before long, the whole village started calling our family the Tuttazzurr family, and I myself became known as Giuan Tuttazzurr. Blue marked our home, but also my identity and my story—etched in memory and in name.

The Illusion of Color in Astrophysics


Study on Colors in Astrophysics – Ongoing Research

Under specific atmospheric conditions and with the technological tools employed, stars or planets may appear to emit green or blue light to some observers. However, as illustrated in the accompanying diagram, this is often nothing more than an optical illusion. The blue region seen in the diagram is actually a medium gray, entirely desaturated. You can verify this by using Photoshop’s color picker tool (or an analogous method) to check the true color values.

This phenomenon raises interesting questions about how color perception in astrophysics can be influenced by both atmospheric effects and the limitations of observational tools. How much of what we “see” in the cosmos is truly the color of the objects themselves, and how much is a product of the interaction between light, our atmosphere, and the instruments we use to detect it?

The Enigmatic Color of the Sun

Is yellow the true color of the sun? Our sun emits a broad spectrum of radiation, including visible light, which is crucial for life on Earth. In the vacuum of space, the sun appears white because it emits light across all wavelengths fairly evenly. However, when this light enters our atmosphere, it encounters air molecules and particles that scatter shorter wavelengths—primarily blue light—more effectively than longer wavelengths like red and yellow.

color of the sun

Simultaneous Color Contrast Explained…

Consider a small, clear disc placed against a blue background. The disc may appear slightly yellow due to the influence of the blue light surrounding it. This visual effect is similar to how we perceive the sun against the blue sky.In essence, while the sun itself emits white light, our atmosphere alters its appearance, leading us to see it as yellowish or orangish at times.

Additionally, not all species perceive colors in the same way. Different animals have varying sensitivities to wavelengths of light. This means their experience of color and light can be quite different from ours.

For more fun facts about color perception and optical illusions, visit Archimedes Lab.

Amazing Brightness Constancy Effect

Look carefully at the saw-tooth wave patterns on this picture. Is the background of the picture uniformly gray or are there different shades of gray?

Kolozanges (2013-2021), © Gianni A. Sarcone

Brightness constancy makes some vertical strips look darker, when in fact the gray background is all the same shade of gray.

This op art work is available as prints and canvases from my official online Gallery.

Is Magenta a Real Color?

Most of us are familiar with magenta — it’s a kind of purplish-red that exists between blue and red on color wheels (color wheels don’t accurately represent the physics of photons, but they represent the philosophical reality: color is a human construct that helps us interpret wavelengths to better understand our world).

The odd thing about color vision is that magenta (or pink) color is not in the spectrum of colors, meaning it cannot be generated by a single wavelength of light. Our brains interpret the color sensation of magenta/pink as ‘absence’ of green.

Source: https://www.archimedes-lab.org/Gallery/new_optical_illusions/pages/10n-Pink_rose.html

magenta

You Can’t Possibly Color This!

You_cant_possibly_color

An Impossible Optical Illusion Activity Book

No mere coloring book, You Can’t Possibly Color This! is an eye-spinning experience that will inspire and astound. That’s because you’ll be coloring in optical illusions — things that can only exist on the page. With a just a few tips, you’ll be coloring in things that will bulge, expand, and even rotate. Other objects will leave you confused as you try to figure out the “trick,” while mandalas, complex patterns, and labyrinths will mesmerize you. Also included are fun activities for drawing and creating your own optical illusions.

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Illusive Op Art Skulls

I am currently working on new “neon color spreading” effects. Have a look at the pictures below… Though you perceive fluorescent grinning skulls, the vertical white stripes don’t contain any color at all, they are uniformly white! The trick lies on the fact that some black lines have very thin color edges. This illusory shading effect is also known as “subjective transparency” or “Tron effect”.

The neon color effect was first observed by D. Varin in 1971. The human ability to perceive a neon effect may be a remnant of the development of our power of sight under water at extreme depths, where light is very poor.

My Op Art Skulls are available as prints and t-shirts from my online store.

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