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What Is Diamond Brilliance? Does It Make The Diamond Shine?

What Is Diamond Brilliance? Does It Make The Diamond Shine?

When you think about diamonds, the first thing that springs to mind is probably their unmatched shine. A few terms are used to describe different sources of diamond’s sparkle, and one you’re most likely to come across is brilliance.

So, what is diamond brilliance, and is it the only factor contributing to the diamond’s glimmer?

We’ve prepared all the answers – so, let’s dig in!

Do Diamonds Shine When They’re Found?

The answer to this question involves digging – and we mean that quite literally!

Diamonds come to light in a glowing medium (lava) but don’t shine themselves at this stage. No one knows for sure how long it takes for diamonds to form, but we do know they originate about 100 miles below the Earth’s surface – in the upper mantle.

They came to be visible after a historical volcano eruption that happened long ago – and that we haven’t been around to witness. These are the main reasons scientists know so little about their formation and can only analyze what they see: Stones embedded in now cooled molten lava rock called magma.

The majority of all gemstones come in the form of crystals grown together – called aggregates, and there are many different descriptions of this appearance.

That means diamonds have to be mined and don’t look impressive when found – they have a rough, opaque coat that needs processing first. They genuinely aren’t much to look at when they’re first mined. 

Be patient; we’ll get to that in just a bit! 

Read More: Can Lava Destroy A Diamond?

What Causes A Diamond To Shine?

A diamond has to “see the light of day” since every gem owes its color, brilliance, fire, sparkle – and fluorescence, in some cases – to the play of light! 

Observing the light’s dance-like movements enabled jewelers to determine which shape and proportions bring out the maximum shine in a specific diamond. 

That is achieved by cutting and polishing – but we’ll get to that later. 

For now, we need to know that the surface of a finished diamond is covered in facets. A smaller portion of the light hitting the diamond bounces off the facets – but the remaining light manages to go through them and aim for the center of the gem.

These rays bounce off of the diamond’s internal walls, as they would if you were to place many mirrors in a room and arrange them in such a way that they reflect that light ray amongst each other. 

Usually, after a few “bounces,” the light wave finds a straight way out through the facets, and at this time, dispersion of the light happens. 

This pathway of light challenges the cutter’s experience in maneuvering the light movement and differentiates the “shining” terms outlined below.


It’s achieved by directing the light waves in a wanted direction after entering the diamond. 

As previously described, the exact spot the light bounces off is determined by the cutter’s skill in sculpting the diamond’s facets and essentially “bending” the light waves as they mold the gem. 

The goal is to cut the facets so that they reflect rays from any angle up to the top of the diamond – so that it lines up with the viewer’s line of sight. If that’s accomplished, the resulting reflection is called brilliance.

But there are a few more critical light “plays” going within a diamond.


Fire is used to describe the colored flashes of light that “live” inside a diamond. In other words, that’s the mentioned dispersion of light – and diamonds play this reflection trick better than any other substance.

It happens when the rays bounce off of the internal walls of the gem, as described.

That ends up looking dramatic since white light is made of rainbow colors, and each color – red, orange, yellow, green, blue, and violet – bends and reflects differently. These colors separate as the light wave goes further and disperse within a diamond. 

About two to three “bounces” is enough to make a visible rainbow! 

Related Read: Does A Real Diamond Sparkle Rainbow?

Sparkle Or Scintillation 

The cutter must direct the rays up to the top for brilliance but also across the diamond body – so that it looks as if they’re “skipping” between the internal walls. Such alignment of the light waves is referred to as sparkle. 

It’s often neglected when it comes to diamond topics since it’s relatively similar to brilliance. But we can see that a subtle difference – such as this one – makes a whole new phenomenon.

Learn More: Diamond Scintillation: Guide To Diamond’s Light Performance


Some diamonds can give off a usually blue glow that lasts as long as the UV light is turned on – a property known as diamond fluorescence

That said, some gems can even glow for years – but that’s called phosphorescence. The famous Hope Diamond, for instance, has this magical ability. 

We owe these two phenomenons to impurities inside the gem that react with day-light photons. We’ve covered this fascinating topic here, so feel free to check it out.

See Also: Can Ultraviolet (UV) Light Destroy A Diamond?

What’s The Process Of Cutting Diamonds?

The cut is the most important out of the four C’s since it directly impacts every other aspect of the given stone. So, let’s discuss it a bit further!

History Of Cutting And Polishing – Today’s Influence

If you want to understand diamond cutting, you have to return to its origin. 

It’s engraved in Indian literature and manuscripts – as India was always regarded as the natural, ancient home of diamonds. That’s where they were first found. 

Ancient artifacts suggest that diamonds were known and used in the Buddhist period, about the fourth century B.C. – but there is no literature revealing when exactly they started cutting them, so they must’ve been limited to polishing.

For a long time, those were equivalent terms.

Tavernier, a French jeweler, has given the very first description of cut diamonds. He traveled to India back in 1665, and he found that the Indians were polishing over the natural faces of gems.   

They also had the knowledge of grinding them and removing spots or grains. If the impurity was too deep, they resorted to hiding it by covering that part with a significant number of facets. 

Tavernier noted there were European professionals that received the most prominent stones for processing. Still, it’s unknown whether they perfected the trade with the help of Indian artisans – or they came there with superior knowledge. 

So, the Indian diamond-cutting style marked some of the most famous gems to date – like the Koh-i-Nor.

That’s how the modern norm was created – when cutting a stone, ensure the minimal amount is removed. It was, in a sense, influenced by primitive polishing – using facets for coverage while following the gem’s natural shape. 

Read More: Which Country Is Famous For Diamond Cutting?

When Did Cutting And Polishing Become Sophisticated?

Diamond cutting was taken seriously in Europe, too. In Germany, in 1375, a guild was formed by three leading artisans – and admission was granted only after a six-year apprenticeship – but their methods remain unknown. 

In the 15th century, women started the trend of wearing diamonds in Europe! 

Before that moment, diamonds were exclusive royal ornaments and fashion reserved only for princes. 

That was the turnover that conditioned mass “production” of jewels – and forced the masters of the art to strive towards perfecting cutting and polishing on a much larger scale.

What Was The Goal Of These Processes?

It’s simple; the goal was to achieve brilliance!

And the fateful moment was discovering the first tool in diamond cutting – the cutting wheel. Do not let the name fool you, though; it’s essentially used for polishing.  

Powder leftovers from cutting the diamond were used, and the diamond was held with primitive iron polishing wheels invented by Lodewyk (Louis) van Bercken in 1476. 

The process, for the most part, works similarly today. 

This discovery was necessary to achieve today’s symmetry in diamond shapes, although the actual polishing process was invented a century earlier. 

Also, it influenced the variety of diamond shapes produced. On this path, it was discovered that the circular – or round shape – created by gradually shrinking the gem’s corners offers maximum brilliance. 

But there is a downside to such a modern method: The weight of a diamond, cut and polished, could make a loss of 52% of the initial weight – even in favorable cases. 

One could argue that set European crafters apart from those in India – they constantly strived to achieve more incredible brilliance and fire, no matter the quantity of the lost material.

The Today’s Science

There is one reputable standard that had held its ground since 1919, when Marcel Tolkowsky, a third-generation diamond cutter and student of mechanical engineering, came up with a perfect formula. 

His findings still stand as the objective, measurable standard of perfect diamonds.

This ideal is called the Brilliant Cut and offers maximum fire and brilliancy. The key is making 58 facets, cut in precisely mathematically determined angles, to provide a maximum play of light – a complete reflection and refraction of rays. 

But one must be vigilant since too much light refraction in a small stone could reduce clarity – a property that’s critical when it comes to diamond value!

How It’s Done 

Remember how we said diamonds first have an unsightly appearance? Well, in order to unleash a diamond’s brilliance, that has to be dealt with first:

The ore must be crushed, and the rough diamond is separated from it. Then they’re measured and divided before the primary process – cutting.

Cutting a diamond is generally a four-step process:

  1. Cleaving – First, a diamond has to become a manageable size by cleaving alongside the diamond’s tetrahedral plane, where it’s the weakest. The diamond is positioned in wax or cement mold, which holds it in place, and the cutter uses a sharp steel blade in a groove to cut the stone in two.
  2. Sawing – The cutter uses a rotating phosphor-bronze blade to cut the diamond in the places where it’s not weak. That is when they decide which part will become the table and which the girdle. 
  3. Cutting/Bruitting – Bruitting is the term for cutting by hand; “cutting” means it’s done by a machine. In both cases, another diamond is always used – since only a diamond could cut a diamond. This stage is also when the cutter decides on the shape. 
  4. Polishing – A rotating wheel that contains abrasive diamond powder is used to create a smooth finish that allows the optimum light to enter the gem.

The cut is one of the famous four C’s considered when appraising a diamond – along with color, clarity, and carat. 

But besides the all-important facet sculpting, one more factor helps a diamond shine bright, and without this feature, the cutting would indeed have a lesser effect – or none whatsoever. We are talking about the diamond itself! 

The electrons in the diamond’s tight carbon structure slow the light waves down, maximizing the brilliance and the other “light play” mentioned. And that’s something that makes diamonds stand out among gemstones.

How You Can Maintain Brilliance At Home – Bits Of Advice

Diamonds are known to be natural magnets for grease – so, even holding a diamond with your fingers could lead to enough build-up on its surface to reduce its brilliance and fire. 

There are ways to change that: 

  • You can clean it once or twice a week, using water and mild dish soap. We recommend using a toothbrush to remove eventual remaining dirt in the hard-to-reach places gently. Then rinse the piece with clean water and dry with a soft, lint-free cloth. Don’t forget to close the drain if you’re trying this over a sink!
  • Don’t use chlorine bleach and abrasives, such as toothpaste or household cleaners; these harsh chemicals could damage the jewelry setting.
  • You might’ve heard about ultrasonic cleaners that use low frequencies to cause vibrating fluids that shake the dirt off the gem. Use it carefully – preferably in a professional setting – since it can cause loose stones, if there are any, to fall out of the jewelry. We’d suggest consulting your jeweler first.

You can learn how to take care of your diamond here.

Diamond Brilliance: A Quick Recap 

If you’ve made it this far, you indeed have the answer to the main question, “What is diamond brilliance?” 

As we previously stated – fire, scintillation, and fluorescence all have a significant role in playing with light waves. And these processes essentially determine how bright your diamond will shine!

It’s a long process to turn a rough, opaque stone into a glimmery gem we first think of – and the step that determines how all these processes will permanently play out in a diamond is cutting.

Before deciding on a diamond, always visit a reputable jeweler and look at the gem’s certificate; it holds the information about the four C’s – and much more. 

Ensure the certificate notes VG (Very Good) or EX (Excellent) for the diamond’s cut grade. And if you’re going for the win, choose diamonds that feature an excellent polish, finish, and cut – the ones called “Triple X” diamonds.

Oh, and one more thing: 

How well you take care of the gem dictates how much brilliance you’ll see. So, take care of your diamond at home, using a simple, non-costly cleaning routine to ensure that you’ll have a lovely diamond jewelry piece for years to come!