Skip to Content

Why are some objects black?

By: Author Color With Leo

Why are some objects black?

There are a few main reasons why some objects appear black in color:

Light absorption

The primary reason certain objects are black is that they absorb most visible wavelengths of light rather than reflecting them to our eyes. When light hits an object, it can either be reflected, transmitted, or absorbed. Objects that appear black absorb most of the visible light spectrum, reflecting very little back to our eyes.

For example, a black T-shirt or black car looks dark because the material and pigments making up those objects absorb most light across the visible wavelengths instead of bouncing it back. This gives the objects a dark, black look.

Pigments

Pigments are another factor that contribute to an object looking black. Many black substances contain carbon-based pigments such as charcoal or lampblack. These pigments strongly absorb visible light wavelengths, causing the material to look black.

Carbon black and ivory black are two common pigments used in paints, inks, plastics, and other materials to create a black color. The pigment particles absorb light energy rather than reflect it, creating that dark black appearance.

Surface finish

How smooth or rough an object’s surface is can also affect whether it looks black. Surfaces with very smooth finishes tend to reflect more light, while rough, uneven surfaces scatter and absorb light.

For example, a piece of black paper looks black partly because the fibers making up the paper have a rougher surface that scatters light in all directions. A smooth black plastic surface, on the other hand, would likely reflect more light and not look as dark.

Multiple internal reflections

When light enters certain substances, it can bounce around and reflect off the internal structure multiple times. Each time the light reflects internally, more of it gets absorbed.

Jet, for example, is a black substance formed from fossilized wood under high pressure. It looks black because when light enters jet, it reflects internally off its complex molecular structure multiple times, getting more absorbed each time until almost no light comes back out.

What makes colors black

When we see a color as black, it means that material is absorbing most visible light wavelengths and reflecting very little back to our eyes. This makes it look dark.

Different materials can appear black by absorbing light in various ways:

  • Pigments – Carbon-based pigments like charcoal or lampblack absorb light.
  • Molecular properties – Materials with certain internal molecular structures absorb more light.
  • Surface texture – Rough or uneven surfaces scatter light in all directions.
  • Dyes/colorants – Black dyes and colorants are engineered to absorb broad spectrum light.

So while different substances use various methods to absorb light, the net result is that very little visible light reflects back, creating a black appearance.

Types of black colors

There are different shades and variations of black colors, including:

  • Jet black – A very deep, dark black with little light reflection or sheen.
  • Ebony black – Slightly lighter and warmer than jet black, with a bit more brown.
  • Charcoal black – Dark black with a grayish tint.
  • Onyx black – Deep, rich black that may have a subtle transparent sheen.
  • Matte black – Flat black with no reflective gloss or sheen.

The exact shade of black depends on factors like pigments used, surface gloss, and microscopic texture. But in all cases, the underlying principle is that the material absorbs most visible light.

Common black objects and materials

Many everyday objects and materials around us appear black. Some common examples include:

  • Tires
  • Oil/tar
  • Charcoal
  • Black plastics and rubbers
  • Textiles like black cotton or wool
  • Carbon paper
  • Iron oxides
  • Obsidian rock
  • printer ink/toner
  • Electrical wires insulation

These substances contain pigments, dyes, or have surface properties that result in the absorption of most visible light, creating a black appearance.

Black in nature

In nature, black coloration occurs both in the animal and plant world for various functions:

  • Camouflage – Black fur or feathers can blend into shadows and dark environments.
  • Signaling – Some animals use black patterns to signal warnings to predators.
  • Heat absorption – Black surfaces absorb heat from sunlight.
  • Seed/fruit dispersal – Black fruits and seeds absorb light to aid in germination and growth.

Different mechanisms create black in nature, like melanin pigments, microscopic structural layers, surface textures, and carbon-based biomolecules.

Black and art

Black has been an important color in art through history, conveying concepts like power, mystery, and solemnity. Some artistic uses of the color black include:

  • Charcoal drawing and sketches
  • India ink and calligraphy
  • Oil or acrylic black paint
  • Photographic black and white photography
  • Prints/etchings using black inks
  • Ironwork and blacksmith crafts
  • Pottery and ceramic vessels painted black

Artists can create different black shades by blending pigments, using different surface treatments, or adjusting lighting on black materials.

Why space looks black

Space appears black for a few key reasons:

  • Empty space has no light sources to reflect light.
  • Stars and galaxies are very distant, so only a tiny fraction of their light reaches us.
  • Gas and dust absorb light traveling through space.
  • The universe is expanding, redshifting light to lower frequencies.

So while space contains stars and galaxies emitting light, the vast emptiness and distances mean very little light actually reaches our eyes, leading to space looking black even with a telescope.

Advantages of the color black

There are some useful properties and advantages of the color black in certain applications:

  • Heat absorption – Black surfaces readily absorb heat from sunlight and sources like fires or stoves.
  • Concealment – Black makes objects harder to see against darker backgrounds.
  • Enhanced contrast – Black backgrounds boost the contrast and visibility of brighter colors placed against them.
  • Solemn mood – Black evokes feelings of solemnity, mystery, or elegance.
  • Print legibility – Black ink provides high contrast for printed text on white pages.

Understanding these useful black material properties helps explain their prevalence in applications from solar heating to formal attire.

Disadvantages of black

There are also some disadvantages or undesirable effects related to the color black in certain situations:

  • Black clothing can get hot in sunlight compared to lighter colors.
  • Black paint can make spaces feel smaller due to light absorption.
  • Black objects are harder to see at nighttime than reflective colors.
  • Black gives off a more serious or depressing mood in some cultural contexts.
  • Black smudges and marks more easily show on lighter surfaces.

While black has its benefits, these limitations are worth considering when choosing colors for clothing, design, or visibility needs.

Frequently Asked Questions

Why do some black materials fade over time?

Black materials can fade when exposed to sunlight or chemical reactions over time. UV rays from the sun can break down black pigments, dyes, or surface coatings that initially absorbed light. Chemical changes to the molecular structure can also reduce light absorption. Regular cleaning and limiting sun exposure helps retain deep black color.

Can true black exist without any light reflection?

A material that reflected absolutely no light at all would appear void-like to our eyes rather than having visible black color. Vantablack comes close by reflecting only 0.036% of light. But true 100% light absorption is not thought to be possible for natural materials, as there will always be some faint surface reflection.

Why do some animals have black skin, fur, or feathers?

In nature, black coloration provides several survival advantages for animals. Dark pigmentation helps absorb heat from the sun in cold climates. It provides camouflage in dark environments. Black patterns may serve as warning signals to scare off predators. Melanin black pigmentation also offers UV light protection.

Is black heat absorption related to the color itself?

Black surfaces absorb heat not because of the black color per se, but due to physical properties that allow the material to readily accept and retain energy from light across the electromagnetic spectrum, including infrared. The microstructure, rather than visible color, determines heat absorption.

Why is outer space black if stars emit light?

While stars emit visible light, space itself is mostly empty, so there is no background surface to reflect that light to our eyes. The tiny fraction of starlight that reaches us is lost against the vast darkness. Cosmic dust and the universe’s expansion also limit observable light.

Conclusion

In summary, black is the visual perception of objects absorbing most visible light wavelengths. Different materials appear black due to pigments, dyes, microstructures, internal reflections, and surface properties that inhibit light reflection. Understanding the mechanisms behind black allows us to take advantage of its useful properties in applications from clothing to industrial coatings.