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Do Diamonds Emit Light?

Do Diamonds Emit Light?

Did you have a chance to look at your diamond a little better? If so, then you probably thought about how they tend to shine brighter under certain lighting.

That’s a fact – but people often get carried away by the dazzling sparkle. Some of them even think that diamonds can glow in the dark. Can they, though? We’ll get to that soon enough, but we need to introduce this topic with a well-thought-out question that will serve as a basis: Do diamonds emit light? The short answer to this would be – not all of them. 

Most diamonds reflect light and shine under room lighting. On the other hand, fluorescent diamonds have the ability to emit blue light – but only under certain circumstances.

Since explaining the question above takes a little more than just a few sentences, it would be best to keep scrolling through this article. We’re going to talk about what the shine of your diamond depends on, what makes fluorescent diamonds unique, and share more interesting information.

Read on!

Most Diamonds Catch And Reflect Light

Without light, your diamond is just another gemstone. We know that sounds basic and kind of disappointing. But for your diamond to shine, you need any kind of room lighting.

What does that tell you? It tells you that diamonds can’t emit light on their own; they just draw and reflect it. That strictly depends on the following factors:

  • Reflection
  • Refraction
  • Dispersion

Learn More: Diamond Refractive Index: Do Diamonds Disappear In Water?

Let’s clear this up.

First, the reflection of light. That is the easiest to understand when it comes to flat surfaces. Diamond facets are flat surfaces, and with their help, a diamond can reflect light. For example, if the light hits the facet at an angle of 30 degrees from the left, it’ll bounce off at a 30-degree angle to the right.

But the reflection works a little differently when it comes to curved surfaces, and the shine will be of different intensity. Here, your diamond will attract different rays of light, but they will bounce off at the same point. The effect of this, when you look at the surface on which it bounces, gives you the impression of a magnifying glass.

The second factor is the refraction of light. It’s important because it can help us determine the quality of the cut. 

Refraction, as well as reflection, occurs on your diamond’s facets or girdle. It is not a direct light reflection but the bending of light rays. Refraction happens every time light passes from one transparent source to another. That gives us the ability to use magnifying glasses and lenses.

Once you understand what refraction is, you can use this knowledge to examine your gem for any possible surface flaws – such as scratches and inclusions.

The last factor would be diamond dispersion, or otherwise known as “fire.”

The rainbow you thought you saw inside your diamond is a dispersion of light. It happens when light passes through a diamond and temporarily creates colors. It’s important to know that these are not actual colors in your diamond; they are just wavelengths.

For example, a red color wave is longer, and it passes through a diamond faster than a blue one. That might be a matter of aesthetics, but gemologists look at it from a different angle. Using dispersion, experts can measure the RI (refractive index) of diamonds.

Okay, time for a short recap: A refractive index is a measurement by which you can determine how fast rays of light travel from point A to point B. It can also help you detect how much light is bent or refracted. Experts can measure the dispersion of a diamond by using a spectrometer. And the larger the measurement, the more colors the diamond displays.

To measure the dispersion of light, gemologists use red and violet light, and the difference between the two represents a diamond’s absolute dispersion. On that note, the typical diamond dispersion equals 0.044.

How does color affect the diamond’s dispersion?

With transparent diamonds, this does not matter as much. But when it comes to colored diamonds such as yellow or pink, the surface affects the wavelength that enters the gem. That will affect it – but it will not drastically change the appearance of your diamond.

See Also: Do Black Diamonds Reflect Light And Sparkle?

Scintillation, Birefringence, And Pleochroism

Scintillation, birefringence, and pleochroism are three additional terms that often tend to be confused with dispersion. Since they are crucial for your diamond, we figured they deserve mention here, too.

Scintillation is just another name for diamond sparkle. It happens during reflections and light shifts. The result is a mosaic look, and it can affect the cut.

Diamonds that have the ability to split light in two or more directions are double-refractive

That is also called gemstone birefringence, and it is calculated using the RI or the refractive index (RI). Diamonds with an isometric cubic system cannot polarize light, which means they do not have birefringence.

Diamond pleochroism is actually the result of color dispersion. It means that a diamond can show two or three colors from different angles. While this is a typical feature for some gems, with others, it’s extremely hard to notice.

It works like this: Diachronic diamonds show two and trichroic three colors. It’s certainly nice to look at, but it can help you when it comes to the diamond examination, too. 

The number of colors and their intensity can help in determining the crystalline structure. If you have an unknown stone in your possession and you know a thing or two about gems, observing pleochroism can help classify it.

What’s The Difference Between Dichroism And Pleochroism?

People often confuse these two terms – so, let’s clarify.

Dichroism translates into “two-colores,” and it represents just that. It is the ability of crystals and minerals to show two different colors when viewed from different angles.

Pleochroism, on the other hand, represents the ability of crystals and minerals to represent different colors when viewed from different angles. In fact, pleochroism directly translates as “more-colores.”

What can we conclude from all this?

It is obvious that light and color play a huge role in the reflection, refraction, and dispersion of light waves and diamonds. That affects the appearance of the diamond you’re looking at, but it can also help gemologists evaluate their cut and categorize them.

Fluorescent Diamonds – Do They Exist?

They exist, but they are not so common. It is estimated that 25-35% of diamonds show some level of fluorescence. What exactly is fluorescence in diamonds, and how does it work?

The fluorescence of a gem is its ability to emit visible and colorful rays of light under certain circumstances, including UV lights or lamps. The most common fluorescent color is a shade of blue, but with some diamonds, this can be realized through yellow or possibly even green.

That is an essential feature if you’re considering buying a diamond. In addition to cut, clarity, color, and carat, gemologists measure the intensity of fluorescence. Diamond fluorescence is measured as follows:

  • Strong
  • Medium
  • Faint
  • None

Fluorescence can affect the price and value of a diamond.

If it is a transparent diamond we’re talking about, it is generally desirable that it doesn’t show high levels of fluorescence. That could reduce its value in the market. 

If you want to buy diamonds like this in jewelry shops, you could probably get some kind of discount, which is okay if you’re not looking to spend too much money.

On the other hand, colored diamonds that emit this bright light are precious and are often sold at premium prices. 

Why is this? Because the blue fluorescent color fits pretty nicely with the undertone of the diamond and it makes it look more attractive. Fluorescent diamond prices can range anywhere from $4,00 to $9,000.

Here’s a tip: Don’t rely on online shopping. The Internet is a breeding ground for scams, and you could easily get a low-quality diamond – or even worse, a glass copy.

Using UV Light To Spot A Fake Diamond

UV light does not only affect the price and value of a diamond. Using black light also allows us to determine whether the diamond we are looking at is real or fake. All you need for this test is a functioning UV lamp and a diamond. 

The first thing you will do is turn off the other lights and leave only the UV light in the room. Next, put the diamond under the UV light, and take a closer look. What do you see? Blue light or something else?

If you see a blue light, you are probably looking at a real diamond. Genuine diamonds will emit blue light as long as they are under that lamp. The moment you turn off the light, the diamond will no longer be fluorescent.

Read Also:

How To Make Your Diamond Sparkle More?

All this talk about diamonds shining has certainly made you wonder, is there a way to make your diamond sparkle more? There’s not just one, but several ways in which you can do this.

Soaking Your Diamond In Warm Water

The easiest way to make your diamond sparkle is to clean it regularly. It can be done by soaking them in water – but not in your tub or anything with a drain, for that matter.

Take a small cup or basin, depending on how much jewelry you want to clean – and fill it with warm water. Next, add some light detergent, and stir the mixture with your hands. Some people even use baking soda as an alternative.

Let it sit for a few minutes, and then take it out. The best option would be letting the diamond dry on its own, but wipe it with a towel or cloth if you don’t have the time.

Using Brushes To Polish Your Diamond

You’ve probably seen jewelers that have at least ten different brushes in their drawers that they use for cleaning and polishing diamonds.

The good news’s that you don’t have to buy expensive sets of brushes to clean your gem at home. All you need is one brush that is meant for this purpose. From time to time, when you notice that dust has accumulated, brush your diamond for a few minutes.

The key is to clean your diamond regularly before the dirt accumulates to the point where it becomes impossible to clean!

Using Glass Cleaner 

You need two things for this method – a glass cleaner mixture and a toothbrush.

As we said, when cleaning your diamonds, you shouldn’t use strong chemicals because they can cause a counter effect. Luckily, glass cleaners do not fall into this category and are often used as an alternative to cleaning, in addition to baking soda.

You have to spray your diamond a few times and scrub it with your toothbrush. Don’t press the diamond too hard, though. After scrubbing for a couple of minutes, let it sit for 10-15 minutes and rinse thoroughly.

Final Thoughts

That’s about it; we’ve mentioned everything there is about diamonds and light. We’ve even added some helpful information that’ll undoubtedly come in handy. Let’s go over everything once again:

First off, we concluded that not all diamonds emit light. Most diamonds only catch and reflect light. Only about 25% of diamonds can emit light – and these are fluorescent diamonds.

When it comes to emitting light, it is essential to distinguish between reflection, refraction, and dispersion. Determining how light is received and reflected from your diamond is done by calculating the refractive index (RI).

On the other hand, fluorescent diamonds emit blue light in a specific environment. 

That involves examining such diamonds under UV light. It can also help when determining whether your diamond is real or fake. Keep in mind that blue is not the only fluorescent light you can see; you can also look for green or yellow.

If you want your diamond to sparkle more, you can achieve this in several ways, but most of them involve regular cleaning. A common way you can do this is by soaking your diamond in warm water with a detergent or spraying it with regular glass cleaner and scrubbing it with a toothbrush.

That’s all for now. Until next time!

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