Diamond Cut: The Ultimate Newbie Guide

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My Bottom Line Recommendation

Since there is no point in getting a dull diamond that shows no sparkle, we must prioritize cut to a certain degree. I created two filter settings you can use right now, click them and see the diamonds available:

  1. If you want to strike the best balance between all factors, this is the setting for you.

  2. If you want to narrow diamond the options to those which show the strongest brilliance, fire, and scintillation, use those settings

  3. If you are after a premium round diamond, take a peek at this diamond collection. These diamonds represent the top 1% of round diamonds, offering the highest light performance and the most jaw-dropping wow factor

My top picks for diamond cut

1. Best balance

1.10 Carat I VS1

2. Largest diamond

1.23 Carat J VS2 Hearts & Arrows Cut

3. Most premium

1.046 Carat D VS1 Hearts & Arrows Cut

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Table of Contents

The Definition of Diamond Cut

What is a diamond cut? Unveiling the meaning

When we talk about a diamond’s cut, we’re discussing how well the diamond’s facets—those tiny, cut planes on the diamond surface—play with light. These facets are meticulously crafted to maximize the return of light, giving a diamond its unique dazzle.

Each of these tiny surfaces, or facets, acts like a mirror, bending and bouncing light in a spectacular show of brilliance. The magic of a diamond’s beauty and value often lies in the arrangement and proportions of these facets. Think of the cut as a measure of how well-balanced these dimensions are—for example, how the diamond’s diameter compares to its depth.

The cut is crucial—it influences the diamond’s overall appeal. A diamond cut to perfection will brilliantly reflect and bend light, creating that distinctive spark we all love. Achieving this level of accuracy demands skilled craftspeople who understand the dance of light within diamonds and prioritize brilliance over carat weight and size.

Separating cut from shape: A common misconception

Round brilliant cut diamond, princess cut diamond, asscher cut diamond, radiant cut diamond (and so on…) are all shapes – not cuts.

Diamond shape, quite simply, refers to the outward appearance or the outline of a diamond. When viewed from above, the shape could be round, oval, pear, heart, or marquise, to name a few. This aspect is probably the first thing you notice when you look at a diamond, but it’s certainly not the whole picture.

For instance, consider a pear-shaped diamond. This diamond could have various cuts – shallow or deep, dull or brilliant. The shape remains constant (pear), but the cut can vary greatly, affecting the overall brilliance and fire of the diamond.

the-difference-between-shape-and-cut

Understanding the GIA Diamond Cut Grade Scale

The diamond industry follows the GIA cut grading system that grades the diamonds cuts from best to worst:

  1. Excellent Cut: Diamonds with an ‘Excellent’ cut reflect nearly all light that enters, creating unrivaled sparkle.

  2. Very Good Cut: ‘Very Good’ cut diamonds reflect a substantial amount of light, generating a healthy dose of sparkle.

  3. Good Cut: ‘Good’ cut diamonds reflect a decent amount of light, although they might lack the dazzle of higher grades.

  4. Fair Cut: ‘Fair’ cut diamonds reflect only a small to moderate amount of light. They may not be as flashy, but they have their charm.

  5. Poor Cut: ‘Poor’ cut diamonds lose most light out the sides and bottom. Their sparkle falls noticeably short.

To make it simple, an ideal-cut diamond generally shows a stronger brilliance, fire (blue and yellow reflections), and scintillation compared to a lower cut-graded diamond.

There are three main factors that impact the diamond cut quality:

  • Proportions: This refers to the relative sizes and angles of a diamond’s parts. It takes into account how the table size, crown angle, and pavilion depth play together to control how light dances within the diamond.

  • Symmetry: Symmetry is about precision. It checks how well the facets align and intersect. This can include things like misalignment of facets, off-center culets, or wavy girdles.

  • Polish: Polish speaks to the smoothness of a diamond’s surface. It’s a crucial aspect because rough spots could disrupt the journey of light passing through the diamond.

The Triple X Concept

Ever come across the term ‘Triple X’ in the diamond biz? It’s all about diamonds that score an ‘Excellent’ grade across three aspects: cut, symmetry, and polish. Now, there was a time when customers would buy diamonds based solely on their certificate, never laying eyes on the actual rock. That’s when Triple X came into play—it’s a bit of a marketing trick, making you believe a diamond hitting all these ‘Excellent’ marks must be stunning. But don’t be fooled. Plenty of Triple X diamonds fall short in the looks department.

Good Triple X

Bad Triple X

Still, Triple X is a solid starting point for anyone on a diamond hunt. If a low-grade Triple X doesn’t impress, you can bet a diamond with poorer grades would look even worse. So, here’s a tip: keep your eyes on that Triple X and never settle for less when it comes to cut.

Cut Controls The Light Performance

What is a diamond light performance?

Light performance is a term used in gemology to describe how a gemstone, particularly a diamond, interacts with light. It is a critical factor that determines the sparkle and brilliance of a diamond. The way a diamond has been cut and shaped greatly influences its light performance.

Picture this: light hits a well-crafted diamond and embarks on an incredible journey. It bounces within the stone’s facets, refracting and reflecting, before darting back to your eye. This mesmerizing light play results in what we call the diamond’s brilliance, fire, and scintillation. Brilliance paints a picture of intense, radiating white light, while fire breaks the light into a vibrant spectrum of colors. Scintillation, on the other hand, is the shifting dance of light and dark, offering sparkle as the diamond or viewer moves.

What is Brilliance?

So, you’ve got a diamond, right? It’s got all these cuts on it – those are what we call physical facets. They’re like little mirrors, bouncing light around.

Now, when light hits these facets, something magical happens. Even though there’s only a certain number of physical facets on the diamond, it looks like there are loads more tiny lights dancing around inside. Those are what we call virtual facets – they’re like reflections inside the diamond.

And it doesn’t stop there. The light keeps bouncing around inside the diamond, changing direction and reflecting off different facets. And then, boom! All that light comes back together into a super bright, white light that shines out of the diamond right into your eyes.

This whole light show going on inside the diamond makes it look like it’s shining way brighter than you’d expect just from the number of cuts it has. The more cuts, or physical facets, a diamond has, the more dazzling the light show. And that’s what we call brilliance – it’s like a non-stop sparkle party happening right there in your diamond.

What is Fire?

When we look at light, we usually see it as white, right? But did you know it’s actually a mix of all colors? Light travels super fast until it hits something that slows it down.

Diamonds are super good at this. They slow down the light and break it up into all its different colors. When white light goes into a diamond, it bends and bounces off curved edges and the shiny sides and speeds up again.

This cool thing is called dispersion, or sometimes we call it fire. It makes a bunch of colors that make the diamond look alive. The best diamonds show flashes of colors like red, orange, yellow, green, blue, and purple as light bounces around the cut sides. This is what gives diamonds their sparkle and shine.

But, to get this show of colors, the diamond has to be cut just right. The light has to hit at the right angle to show off all the colors. If the diamond isn’t cut right, the light just zips through without making the colors, and we don’t get to see the fire.

What is scintillation?

Okay, so you know when you move a diamond around, and it seems to twinkle like it’s got its own private disco going on? That’s what we call the diamond’s “sparkle”, or in fancier terms, “scintillation”.

So, here’s the lowdown. When you wiggle a diamond about, the cuts on it split white light into a whole rainbow of colors. This creates these bursts of light that dance and twinkle all over the diamond’s surface. At the same time, you get these darker, colored flashes that bounce off the inner facets of the diamond.

Now, the key to a great sparkle is the balance between these lighter and darker areas. It’s like a beautiful dance between light and shadows that creates this overall twinkling effect. But, if the diamond isn’t cut right, some of that light can escape through the bottom, which can dampen the sparkle. So, a well-cut diamond ensures that the dance keeps going, and your diamond keeps sparkling.

The Anatomy of a Diamond Cut

Let’s get to know our diamond’s anatomy a bit better, shall we?

Table: Picture the top flat surface of your diamond – that’s the table. It’s the largest facet of the stone and the window to its inner beauty.

Crown: Sitting just below the table, the crown is the upper part of the diamond. It’s angled and faceted, helping to scatter light into a spectrum of colors.

Girdle: It’s like the diamond’s belt. The girdle is the widest part around the stone, separating the crown from the pavilion.

Pavilion: The pavilion is the bottom half of your diamond, tucked under the girdle. It’s job? To reflect light upwards, giving your diamond that brilliant sparkle.

Culet: This is the tiny facet at the very bottom of the pavilion. Think of it like a diamond’s safety net, preventing damage to the tip.

Depth: The depth refers to the total height of the diamond, from the table down to the culet. The right depth contributes to the diamond’s brilliance, fire, and sparkle. Too deep or too shallow, and your diamond’s inner light show may not shine as bright.

diamond cut anatomy

The magic of light: Understanding how facets interact

For starters, let’s talk about proportions—specifically, pavilion depth. This is the distance from the girdle, the diamond’s ‘equator,’ to the culet, or the pointy bottom. Striking the right balance here is crucial. If the pavilion depth is too shallow or too deep, light can leak out from the sides or bottom. But when it’s just right, it funnels light upwards, enhancing the diamond’s overall brilliance.

But that’s just part of the story. The real stars of the light show are the crown and pavilion angles. The crown, or top of the diamond, catches the light, and its angle determines how much light gets in. If it’s too shallow or too steep, light can escape or reflect improperly, reducing the sparkle.

On the flip side, the pavilion’s angle is the traffic cop, directing how light exits. The goal here is to reflect as much light as possible back up, through the crown and table—the flat top surface—right into your line of sight. If the pavilion’s angle doesn’t hit the mark, you can end up with a diamond that looks dull because light escapes from places it shouldn’t.

So there you have it. The mesmerizing sparkle of a diamond is all about expertly balanced proportions and carefully calculated angles. It’s the hidden science behind every diamond’s captivating light dance.

shallow round diamond cut
ideal cut round diamond
deep round diamond cut

Your Blueprint to Choosing the Perfect Diamond Cut

Having grasped the importance of a diamond’s cut, it’s time to apply that knowledge. Consider this your roadmap to navigating the varied proportions that distinguish each diamond shape. Keep in mind, different shapes reflect light in unique ways. For example, the round brilliant diamond, with its multitude of facets, delivers an enhanced display of brilliance and fire, while the Asscher cut diamond, with its rectangular shape, produces more of a light mirror effect, showcasing less fire but an impressive sparkle.

Round brilliant diamond cuts

Round brilliant diamonds didn’t just stumble upon their name. Sporting a grand total of 58 facets, they take the crown for exhibiting the most sparkles, brilliance, and fire across all diamond forms. That’s what makes them such a hot pick among customers! Believe it or not, they account for a solid 70% of all diamond sales.

The crème de la crème of round diamonds is the coveted ‘hearts and arrows’ cut. Attained by only the top 1% of round diamonds, this cut is synonymous with perfection and symmetry. The outcome is a diamond that outshines others in terms of brilliance, fire, and sparkle. The catch? This diamond commands a 20% premium price. But here’s a pro tip: Use the parameters below to identify a ‘hearts and arrows’ diamond listed as a regular ideal cut, and you might just nab round brilliant cut diamonds below it for 20% less.

Table: 54-60 for a nice cut, 56-58 for high end

Depth: 59-63 for a nice cut, 60-62 for high end

Crown angle: 32-36 for a nice cut, 33.5-35.5 for high end

Pavilion angle: 40.5-41.4 for a nice cut, 40.6-40.8 for high end

Princess cut diamonds

A princess cut diamond uniquely pairs a high light performance round center with a square exterior, leading to a boosted sparkle show.

Table: 66-73

Depth: 71-74

Crown angle: 8-13

Pavilion angle: 55-61

Oval cut diamonds

Generally, a quality oval diamond mirrors the round brilliant diamond at its core, optimizing brilliance and sparkles. So, we’re sticking with similar table and depth recommendations to those for round diamonds:

Table: 54-60

Depth: 59-63

Crown angle: 13.5-15.5

Pavilion angle: 42-44

Pear shape diamond cuts

Pear-shaped diamonds cleverly imitate round-cut diamonds, interacting with light in a similar fashion. Although they may not match the round or oval cut diamond’s light performance, they can still emanate considerable brilliance, fire, and sparkle.

Table: 56-60

Depth: 60-64

Crown angle: 14-16

Pavilion angle: 43.5-44.5

Heart-shaped diamonds

To achieve high light performance, heart-shaped diamonds must be skillfully designed around a round diamond framework. You could even narrow down your search by looking for a 1.10-1.15 ratio.

Table: 54-60

Depth: 59-63

Crown angle: 14-15.5

Pavilion angle: 40.5-43

Marquise cut diamond cuts

Marquise cut diamond cuts

Marquise cut diamonds see a shift in carat weight to the sides, losing the central round illusion. Yet, this shape can still display an impressive amount of brilliance and sparkles.

Table: 57-63.5

Depth: 61.5-66.5

Crown angle: 12.5-16.5

Pavilion angle: 43-45.5

Radiant cut diamond cuts

Radiant cut diamond cuts

A radiant cut diamond can adopt two primary forms. One mirrors a reflection, while the other combines this effect but sustains stronger overall brilliance.

Table: 61-67.5

Depth: 65.3-70.5

Crown angle: 9.5-15

Pavilion angle: 49.5-56

Cushion cut diamond

The cushion cut offers three main variations. It can echo a mirror, blend mirror and brilliance, or even imitate the hearts and arrows cut.

Table: 59.5-70

Depth: 65-70

Crown angle: 12-15.5

Pavilion angle: 44-53

Emerald cut diamond

The emerald cut is an excellent choice for those who love the rectangular shape with a strong mirror effect. It might exhibit less fire due to its fewer facets, but a well-chosen emerald cut can combine brilliance, fire, and sparkles. Be prepared to put in a bit of research!

Table: 57-64.5

Depth: 62-68.4

Crown angle: 11-19

Pavilion angle: 43-52.5

Asscher cut diamond cuts

Asscher cut diamond is the hipster of diamond shapes, it was created for those who like to be unique. Like the other emerald cut diamonds, this cut emphasizes the mirror effect while providing a larger appearance due to its 1:1 ratio.

Table: 54.5-67.5

Depth: 61.6-68.1

Crown angle: 11.5-15.5

Pavilion angle: 45-51

Conclusion - My Personal Experience

Alright, let’s break it down: out of the four c’s in diamond terms – that’s carat, color, clarity, and cut – the cut takes the crown. Imagine the cut as the spark in the diamond’s eye. Without diamond cut sparkles in it, even the biggest and cleanest diamond might look a bit dull. Why own a diamond if it doesn’t twinkle, right?

So, here’s a quick tip when buying a diamond or engagement ring: aim for a diamond rated triple X in cut with the above-mentioned guidelines. Now, your budget will play a big part in your choice. You can get a great cut with other decent features, or you might decide to focus mostly on the cut, even if it means dialing back on the others. This might even lead to a smaller diamond perfect engagement ring, but trust me, its sparkling shine will definitely give you the wow factor you’re after!

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