It is a well-established fact that most of the colors that we see and use today are artificial and chemically prepared. There was a time when we had no choice but to extract pigments of color from natural sources to prepare the dye. However, and apart from this, who knew that blue was once considered as the color of the lower class or purple was associated with royalty? Here is a list of 10 similar surprising and intriguing facts about colors.

1 There is a pigment library in Harvard where sources of rare colors are stored. Some of these sources are wrappings from Egyptian mummies, poisonous metals, and ground-up shells of insects that are now extinct. There are more than 2,500 specimens of such color pigments.

Edward Forbes was a historian and director of the Fog Art Museum at Harvard University from 1909 to 1944. He traveled around the world to collect pigments of colors to authenticate classical Italian paintings.

His collection gradually exceeded 2,500 colors with their unique backstory on their origin, production, use, etc. Forbes was known as the father of art conservation in the US, and his collection is titled the Forbes Pigment Collection.

Today, this legendary collection is used for scientific analysis that helps standard pigments to compare to unknowns. Narayan Khandekar, who is now in charge of the museum and the collection, says that they use instruments on the pigments just like the forensic scientists do.

Khandekar, in the last 10 years, has rebuilt the collection by adding new pigments to it. New pigments have helped him and his staff to analyze 20th century and contemporary art more precisely.

Some of the rarest and most interesting pigments from the Forbes Pigment Collection are synthetic ultramarine, mummy brown, brazilwood, annatto, dragon’s blood, emerald green, etc. (Source)

2 It is commonly believed that water is colorless, but science has shown that pure water is not colorless. It has a slight blue color that becomes deep green as the depth of the water increases. The blue hue is an intrinsic property of water, and the phenomenon is caused by selective absorption and scattering of white light.

Weak absorption in the red part of the visible spectrum causes the light turquoise color in water. The water molecules absorb the red end of the spectrum of the visible light, or to be more detailed, the atoms vibrate and absorb different wavelengths of light and cause the blueness in water.

This intrinsic color property of water can be visible with a simple experiment. You just need to look at a white light source through a long pipe that is filled with pure water. But first, you must make sure that the pipe is closed from both ends with transparent glass.

The blue color is also clearly evident in the glacial ice. This is because glacial ice is much denser and lacks air bubbles because it is subjected to heavy pressure.

However, it is next to impossible to find pure water in natural surroundings. Some chemicals, residues, reflections, and other factors alter its color. Nonetheless, the real color of pure water after filtering and purifying is light blue. (1, 2)

3 Purple was and is still known as the royal color. Back when we were dependent on natural dyes for colors, purple was extracted from sea snails. This made purple the hardest dye to extract and produce, and only royals could afford it. To create just one gram of purple dye, more than 9,000 mollusks were needed.

For centuries, purple has been associated with royalty, power, and wealth. During the Elizabeth era in the second half of the 16th century, Queen Elizabeth I officially banned everyone except close members of the royal family from even wearing it.

Everything rare is naturally associated with royalty, and so was the case with the color purple. Fabrics made with that color were so expensive that only rulers could afford them. Their rarity and expensiveness quickly made them exclusive to the imperial class of Rome, Egypt, and Persia.

Since the ancient emperors, kings, and queens were generally looked upon as gods or descendants of gods, the color purple also started representing spirituality and holiness.

The first dye of making the color originated from the Phoenician trading city of Tyre, which is now modern-day Lebanon. The mollusk from which the dye was extracted was only available in the Tyre region of the Mediterranean Sea.

Things started to change after 1856 when an 18-year-old English chemist, William Perkin, accidentally created a synthetic purple compound. After this event, the color finally became more accessible and affordable to the lower classes. (Source)

4 The human eye can see a limited number of colors, and the ones that are too complex for us to see are called “impossible colors.” The combinations of two colors like blue and yellow or red and green that we cannot see at the same time are impossible colors. They are not visible because of the “opponent process.”

Also known as “forbidden colors,” these are pairs of hues whose light frequencies automatically cancel each other out in the eye. These colors exist but are not visible only because of the limitation of our perception.

When we see a red color stimulus, the opponent neurons in the retina signals the brain that it’s a red light. Now the absence of any stimulus on the same cells signals the brain that it’s a green light. Hence the presence of one color cancels the other, and we cannot see both the colors coming from the same stimulus. The same goes with blue and yellow and some other pairs of colors.  

Some experiments and studies have shown that it may be possible to see the impossible colors. One simple activity to possibly see them is by placing the opponent-colored object right next to the other. Then, cross your eyes so that the two objects overlap, and you’ll see an impossible color.

At the same time, some researchers maintain that the forbidden colors are simply intermediate colors, therefore their existence is still disputed. (1, 2)

5 The color that many of us see in the absence of light is termed “eigengrau.” It is the color that we see in the perfect darkness and is said to be the result of visual signals from the optic nerve. The term was investigated and popularized by German physicist and philosopher Gustav Theodor Fechner.

Fechner is known considerably for his role in the genesis of the measurement of human perception. He was the one to find psychophysics and is believed to be the inspiration for most of the philosophers and scientists in the 20th century.

Eigengrau is the color that we see when we close our eyes or enter total darkness. Most people have described seeing a vague grey field that is usually composed of changing regions of tiny white and black spots in this situation.

This justifies the German definition of the word “eigengrau,” which is “intrinsic gray.” When we see this color, we are actually seeing visual noise that is the static of our retina. This visual noise is a false trigger by the cumulative effect produced by more than 120 million rod cells in our eye.

The noise is omnipresent in our eyes, open or closed, but we don’t see it when we see the world. So only when we close our eyes do we see the intrinsic noise, the true darkness. (Source)