When shopping for a diamond, one of the most sought-after qualities is brilliance – that captivating sparkle that catches the eye and makes a diamond truly shine.

While many factors influence a diamond's brilliance, the cut is arguably the most important.

Understanding which diamond cut offers the best brilliance can help you choose a piece that truly stands out.

Let's explore the options and see which cut maximises that dazzling effect.

Understanding Diamond Brilliance

Before diving into specific cuts, it's important to understand what brilliance actually means.

Brilliance refers to the amount of white light that is reflected back from a diamond to the viewer’s eye.

This reflection gives the diamond its sparkle, making it appear lively and full of light.

A diamond’s ability to achieve maximum brilliance depends largely on its cut – the precise shape and arrangement of its facets.

The quality of the cut can significantly impact a diamond's brilliance, meaning that even a high-quality diamond can appear dull if it is poorly cut.

Factors such as cut grade, symmetry, and proportions play a vital role in determining how well the diamond will reflect light.

Why Diamond Cut Matters for Brilliance

The cut of a diamond is not simply about its shape.

It involves the diamond's proportions, symmetry, and the quality of its polish.

When a diamond is cut to ideal proportions, light entering the stone is reflected and refracted within, then bounced back through the top surface to the viewer’s eye, creating maximum brilliance.

Poorly cut diamonds may leak light through the sides or bottom, reducing their sparkle.

Cut quality is graded from Excellent (or Ideal) to Poor, with Excellent cuts offering the best potential for brilliance.

It’s the combination of angles, depth, table size, and facet alignment that all come together to determine how light behaves inside the diamond.

Which Diamond Cuts Offer the Most Brilliance?

When it comes to maximising brilliance, not all diamond cuts are created equal.

Certain shapes are specifically designed to enhance sparkle, with strategic facet arrangements that optimise light reflection.

Here’s a look at the most popular cuts for brilliance:

Round Brilliant Cut

The round brilliant cut is often considered the king of brilliance.

With 58 facets precisely arranged to reflect light, this cut has been mathematically engineered to deliver maximum sparkle.

Its symmetrical shape allows light to travel through the stone efficiently, creating a stunning display of brilliance.

The round brilliant cut is the most popular choice for engagement rings due to its unmatched sparkle.

Its reputation as the most brilliant diamond shape stems from its perfect proportions, which minimise light leakage.

However, this level of brilliance often comes at a premium, as round diamonds tend to be more expensive than other shapes of the same carat weight.

To explore a selection of round diamonds, check out our round lab-grown diamond search.

Princess Cut

For those who prefer a square or rectangular shape, the princess cut is a fantastic option for brilliance.

It is one of the most popular non-round diamond cuts and features a faceting style that gives it significant sparkle.

While its brilliance may not surpass the round brilliant, it is still a close contender.

The princess cut’s unique arrangement of facets helps to hide any minor inclusions or flaws, making it an excellent choice for those seeking a balance between sparkle and value.

The corners, however, are more prone to chipping compared to the round cut, so a protective setting is often recommended.

Explore our collection by browsing the princess lab-grown diamond search.

Cushion Cut

Cushion cut diamonds, known for their pillow-like shape, come in both brilliant and modified brilliant styles.

A cushion cut with a brilliant faceting pattern can offer a high level of sparkle, though it may not be as bright as a round or princess cut.

The cushion cut has a softer, more romantic look, which appeals to many buyers.

For those wanting to maximise the brilliance of a cushion cut, it’s worth looking for a "cushion brilliant" rather than a "cushion modified" style.

The brilliant style has a faceting pattern closer to that of a round cut, resulting in better light performance.

To find your ideal cushion cut diamond, check out our cushion lab-grown diamond search.

Radiant Cut

The radiant cut combines the best features of the emerald and round cuts, offering an impressive level of brilliance in a square or rectangular shape.

With 70 facets, it has one of the most intricate faceting patterns, which creates a stunning sparkle.

The radiant cut’s versatility makes it suitable for those who appreciate both modern and classic aesthetics.

It’s a great choice for those who prefer angular shapes but still want plenty of sparkle.

The radiant cut also does an excellent job of disguising inclusions and colour, making it a smart option for slightly lower-quality stones.

Browse the radiant lab-grown diamond search to discover more.

Oval Cut

The oval cut is a beautiful and elegant choice that closely resembles the brilliance of a round cut but with a unique elongated shape.

Its extended form can make the diamond appear larger than its actual carat weight, offering great value for those seeking size and sparkle.

Oval cuts can also help to create a slimming effect on the finger, making them a popular choice for engagement rings.

However, oval cuts may exhibit a "bow-tie effect" – a darkened area across the centre of the stone caused by light not reflecting properly.

A well-cut oval will minimise this effect, allowing more brilliance to shine through.

Explore our range of options through the oval lab-grown diamond search.

Other Cuts to Consider

While the cuts mentioned above are renowned for their brilliance, some other shapes also offer decent sparkle.

Marquise, pear, and heart-shaped diamonds can be quite brilliant, but they may exhibit more prominent bow-tie effects or light leakage.

Choosing a high-quality cut grade will help ensure these shapes reflect as much light as possible.

Explore more through our fancy coloured diamonds collection or browse specific shapes such as pear, marquise, and heart-shaped lab-grown diamonds.

Factors That Impact Brilliance Beyond the Cut

While cut shape is crucial for brilliance, other elements also play a role in a diamond’s overall sparkle:

Cut Quality

The quality of a diamond's cut – often graded as Excellent, Very Good, Good, Fair, or Poor – significantly affects brilliance.

An Excellent cut will allow the diamond to reflect the most light, while a Poor cut will result in a duller appearance.

Proportions and Angles

The proportions of the diamond, including the depth, table size, and crown angles, have a major impact on how light is reflected within the stone.

Ideal proportions maximise brilliance by allowing light to bounce inside the diamond before exiting through the top.

Symmetry and Polish

A diamond's symmetry and polish are key to its sparkle.

Poor symmetry can cause light to bounce in unintended directions, while a lack of polish can reduce the diamond’s ability to reflect light.

Why Round Brilliant Cut is the Best for Brilliance

The round brilliant cut consistently stands out as the top choice for those who prioritise brilliance.

Its 58-facet design and perfect proportions are specifically crafted to maximise light performance.

Unlike other shapes, the round cut’s symmetrical design ensures that light is evenly reflected across the entire diamond, resulting in superior brilliance and fire.

However, it’s important to note that this brilliance often comes at a higher price, with round diamonds typically costing more per carat than other shapes.

But for many, the unmatched sparkle of a well-cut round diamond is worth the investment.

Tips for Choosing a Diamond Based on Brilliance

If you're looking for a diamond that maximises brilliance, here are some tips to help guide your decision:

Evaluate Your Preferences and Budget

Determine your preferred shape and consider how much you’re willing to invest in a high-quality cut.

While round diamonds offer the best brilliance, some other cuts may provide a better balance of size, shape, and sparkle for your budget.

Check the Cut Grade on Certification

Always choose diamonds that come with a grading report from reputable labs like GIA or AGS, focusing on the cut grade.

An Excellent or Very Good cut grade is essential for achieving maximum brilliance.

Consider Personal Style and Ring Design

Different diamond cuts complement different settings and styles.

Round and oval cuts are versatile and suit various ring designs, while more angular cuts like princess or radiant may fit contemporary styles better.

Frequently Asked Questions

Which diamond cut is the most brilliant?

The round brilliant cut is the most brilliant, with its optimised 58-facet design maximising light reflection and sparkle.

It consistently outshines other shapes due to its ideal proportions.

Can fancy-shaped diamonds be as brilliant as round cuts?

While fancy-shaped diamonds like princess, oval, and radiant cuts can offer significant brilliance, they generally fall short of the round brilliant’s sparkle.

However, a high-quality cut can still make these shapes appear exceptionally bright.

Does diamond clarity and colour impact brilliance?

While clarity and colour can influence a diamond's overall appearance, cut quality has the most significant impact on brilliance.

That said, higher clarity grades can enhance light performance, as fewer inclusions allow light to pass through more easily.

How can I enhance the brilliance of a diamond?

Choose a high cut grade and opt for diamonds with ideal proportions.

Proper cleaning and maintenance also help maintain sparkle, as dirt and oils can dull the diamond’s surface.

What should I look for in a diamond cut grade?

For maximum brilliance, select a diamond with an Excellent or Ideal cut grade.

These grades indicate that the diamond’s proportions are well-balanced for optimal light performance.