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Does A Real Diamond Sparkle Rainbow?

Does A Real Diamond Sparkle Rainbow?

Although they are one of the hardest materials, diamonds are famously known for their beauty. Diamond’s defining feature has to be their unique sparkle. Every diamond will sparkle in certain lighting conditions. However, a question arises: Does a real diamond sparkle rainbow?

The answer is rather interesting: while the diamond’s outside reflects a rainbow to other surfaces, the color within the diamond should be gray. 

In this article, we’ve covered everything you need to know regarding diamond sparkle. Without further ado, let’s dive in.

What Makes A Diamond Sparkle?

Diamonds sparkle is its ability to take in light and reflect the light back towards the person observing the diamond. Diamond will look more sparkly the more it reflects the light from its facets.

To achieve a sparkly look, diamonds are cut into various shapes with numerous facets. Each of these facets acts like a mirror, as it reflects light from one part of the diamond to another. After that, the light bounces back out of the diamond and creates a gorgeous sparkle.

Since well-cut diamonds can reflect different types of light, it’s important to explain what sparkle means. This diamond’s ability is usually referred to as brilliance and fire.

Brilliance is a diamond’s ability to reflect white light. The more white light a diamond can reflect off its table to the viewer’s eyes, the more brilliant it is. This is the factor that makes a diamond sparkle and looks especially impressive and beautiful.

If a diamond isn’t cut properly, it will appear dim and dull, even in perfect lighting. 

Fire is a diamond’s ability to disperse colored light. A diamond with great fire may give off colored reflection, giving it unique beauty. Fire can take the form of any spectral color, such as red, orange, yellow, green, blue, and violet.

Diamonds with too shallow or too deep cuts won’t refract colored light properly, resulting in a flat appearance.

The last measure of a diamond’s sparkle is how well does a diamond reflect light: when it’s moving, when the person wearing a diamond is moving or a light source is moving. This factor is called scintillation. When a diamond has high scintillation, it has almost no spots where no sparkle occurs.

Finally, polish impacts the ability of a diamond to absorb, refract and reflect the light. The more polished the diamond is, the more sparkle it will have.

Most of the time, diamond cuts with fewer facets are less brilliant than diamond cuts with more facets. Some diamond cuts are specifically designed to have a perfect number of facets for optimal light reflection and brilliance. 

What Color Do Real Diamonds Sparkle?

The way that real diamonds reflect light is unique. The inside of a diamond should sparkle white and gray color. The outside of a real diamond should reflect rainbow colors onto other surfaces. 

On the other hand, fake diamonds have rainbow colors that can be seen inside the diamond as well as on the outside of it. So if you see sparkling rainbow colors inside of your stone, it could be a sign that it’s not a real diamond.

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Which Diamond Cuts Sparkle The Most?

There are various different types of diamond cuts. Let’s take a look at which diamond cuts result in the most sparkle.

Round Brilliant Cut

The sparkliest diamond cut is the round brilliant cut. These diamonds are cut to have 58 facets, which allows the light to enter the diamond and reflect off of every facet to create stunning sparkle. This diamond cut was designed to specifically have the best possible sparkle.

In 1919, an engineer and diamond cutter, Marcel Tolkowsky published a mathematical formula for achieving optimal diamond brilliance. The formula led to the creation of the round brilliant cut, which is the world’s most popular diamond cut.

So if you are looking for the sparkliest, most brilliant diamond possible, the round brilliant cut is the shape you’ll want to choose.

Princes, Radiant, And Cushion Cuts

These cuts are known for their beautiful sparkle. They’re great alternatives as they offer a similar level of brilliance at a lower cost per carat than a round brilliant cut diamond.

The princess cut has a nice ability to chop up and reflect light. In high cut quality, diamonds that are cut into this shape can have absolutely stunning sparkle.

The radiant cut was developed to combine the best aspects of the round brilliant cut and the emerald cut. It has 70 facets that give a great ability to reflect light and create a gorgeous sparkle.

The cushion cut is also good at reflecting light, giving it a high level of fire and brilliance. Even though it doesn’t match the round brilliant cut, it offers a strong sparkle at a lower price per carat. 

Pear, Heart, Oval, And Marquise Cuts

Even though the round brilliant diamond cut has the best sparkle, it’s not the only diamond cut that’s good at taking in and reflecting light. 

There are several other diamond cuts that share characteristics with the round brilliant cut, including a pattern of facets that are invented to reflect as much light as possible.

The pear cut has a similar pattern to the round brilliant cut. In fact, it has 58 facets which allow it to take in and reflect an outstanding amount of light. Unfortunately, many pear shape diamonds are cut badly, resulting in a weak sparkle.

Heart cut diamonds are also cut similarly to round brilliant diamonds, with between 56 and 58 facets. When they’re cut well, they can have a truly magnificent level of fire and brilliance. However, finding a well-cut heart shape diamond can be rather challenging.

As it’s expected from their name, oval diamonds are cut in an oval shape. They have a similar facet pattern to the round brilliant cut. This elongated shape means that this cut is slightly larger than differently cut diamonds of the same carat weight.

56 facets on an oval diamond allow this cut to exhibit beautiful fire and brilliance when it’s cut well.

The marquise cut was invented in the 18th century. interestingly, King Louis XV of France asked for a diamond cut into the shape of his mistress’s lips.

With 56 facets, the marquise cut has a facet pattern similar to a round brilliant cut. A well-cut marquise diamond will exhibit plenty of sparkles.  

Additionally, the marquise cut usually looks slightly larger than differently cut diamonds of the same carat weight. You may want to consider this option if you want a diamond that combines a gorgeous sparkle with an impressive presence.

Emerald And Asscher Cuts 

While gorgeous in their own right, emerald and Asscher cuts aren’t well known for their brilliance. Because of their design and facet pattern, diamonds in these shapes usually aren’t as sparkly as those with a shape based on the brilliant-cut.

Nonetheless, these shapes are prized for their luster and clarity. When they are cut well in a high clarity grade, these diamonds can have an elegant and unique appearance.

There’s More To Sparkle Than Just A Shape

Generally speaking, diamonds with a large number of facets will sparkle more than those with fewer.

However, a diamond’s shape is just one factor out of many that can determine its sparkle intensity. Other factors that affect a diamond’s brilliance, fire, and ability to sparkle are cut quality, depth to table ratio, and length to width ratio.

We’ve shared some tips that will help you chose a diamond with the strongest brilliance and fire.

Choosing An Ideal Cut Diamond

As you may already know, a diamond’s beauty is represented by four factors: cut, color, clarity, and carat weight.

Out of these four factors, the cut quality has the most impact on a diamond’s fire and brilliance. To put it simply, a well-cut diamond will reflect far more light than a poorly cut one, resulting in a much stronger and visible sparkle.

We highly recommend limiting your search to diamonds that have high-quality grades.

Limit your selection to “excellent” if a diamond is graded by GIA when you are looking for a round brilliant cut diamond. These cuts guarantee that the diamond has the right proportions for optimal fire and brilliance.

When it comes to fancy shape diamonds, such as the oval, pear, marquise, and heart cuts, selecting the right diamond can be more challenging. The cut quality of fancy shape diamonds usually can’t be deciphered using just the certification.

If you’re considering a fancy shape diamond, we would recommend using the depth-to-table ratio and length-to-width ratio to avoid purchasing a diamond that won’t reflect light well.

The cut is crucial for optimal sparkle, making it important to take this factor of the four Cs as critically as possible. More than any other factor, the cut of a diamond affects how strongly it sparkles, both in and out of direct light.

Choosing A Setting That Lets In A Lot Of Light

The setting you select for your diamond can have a large impact on how much it sparkles. For optimal fire and brilliance, choosing a prong setting that grants the light to enter into the diamond from every angle and maximize its sparkle.

Bezel settings should be avoided as they cover part of the surface of the diamond. This means they can block light from entering into the diamond and reflecting off of its facets.

Consider A Halo Or Pave Setting For Extra Sparkle

A halo setting features a loop of smaller diamonds that surround the center stone. Because of this, the perceived size of the center diamond is boosted. 

Also, more diamonds mean more sparkle. While picking a halo setting won’t increase the fire and brilliance of your center diamond, the smaller diamonds that make up the halo can also catch light and sparkle on their own.

A pave setting can be a great choice for a more subtle appearance. Pave settings use a line of smaller diamonds that wrap around the band, adding a nice amount of extra sparkle to compliment the center diamond.

Keeping Your Diamond Clean And Properly Cared For

Over time, it’s common for a diamond to pick up residue, dirt, and oil. Even touching a diamond can be more than enough to transfer the natural oil from your hand onto the diamond’s surface, which results in dulling its shine and reducing its brilliance.

For optimal sparkle, make sure you properly care for your diamond ring. If you want your diamond to shine brightly and maximize its brilliance and fire, it’s important to keep it clean.

Learn More: What Sparkles More Than A Diamond?


Let us answer the question “Does a real diamond sparkle rainbow?” once and for all.

Due to the reflection index of the diamond, the reflection and sparkle within the diamond should be in shades of gray. The outside of a diamond should reflect rainbow color onto other surfaces.

However, if your stone has a rainbow color within itself, chances are you’re dealing with a fake diamond.

If you’re looking for the sparkliest diamond there is, we recommend you stick with the round brilliant cut. This cut is designed to sparkle as much as possible, giving a well-cut round brilliant diamond incredible fire and brilliance.

Other diamond shapes that reflect a ton of light, such as the oval, pear, marquise, and heart, can also sparkle beautifully. Other great choices are the princes, radiant, and cushion as they look fantastic when cut to a high standard.

Lastly, there’s more to a diamond’s sparkle than just its shape. Be sure to check for a diamond that has an excellent (GIA) cut grade, as it’s most likely to reflect light in the best possible way and produce stunning sparkle.