Diamond Shapes: A Detailed Guide With FAQ & Buying Tips

Diamond shape: selecting the right stone for your needs...

Next to a diamond’s brilliant sparkle and shine, its shape is typically the first thing people notice about its appearance.🙂 Although round diamonds have a long history in jewelry, gemstone professionals are always testing the limits of cutting and polishing to come up with exciting new shapes that dazzle wearers and bring new levels of scintillation to the beloved gems.

In fact, there are so many diamond shapes to choose from nowadays that it can be a bit dizzying. How can you find the right shape for your style and budget?

👉🏻In this article, we’ll discuss different diamond shapes available on the market and tips for choosing the right shape for your needs as well as answer crucial questions regarding popular options.

A Detailed Guide to Different Diamond Shapes

Clearing up the confusion: Diamond Shape vs. Diamond Cut—What’s the difference?

So what is diamond shape and how does it relate to cut? Although many people use “shape” to describe a diamond’s “cut” and vice versa, the two are completely different characteristics.

Diamond shape refers to the actual figure or outline of the diamond. Gem cutters can cut diamonds into ovals, hearts, squares, and several other shapes to produce unique looks and scintillation.

In contrast, diamond cut refers to the gem cutter’s crucial job of faceting a diamond. Facets create the bright light and rainbows that wearers love to see dancing across the surface of a diamond, and gem cutters must painstakingly shape rough diamonds into faceted stones. Diamond cut is also part of the 4Cs of diamonds, and it measures proportions, culet size and girdle thickness, polish, and symmetry.

Diamond Shape vs. Diamond Cut

However, the two terms are not entirely separate, and both play an important role in a diamond’s fire. Different diamond shapes can be cut in multiple ways and several styles. For instance, a very common cut—the “brilliant cut”—includes 57–58 facets per diamond (depending on whether the culet is pointed or faceted). This cut has the same number of facets regardless of a diamond’s shape. As such, the two terms mean very different things, but they are closely related.

But why is “cut” sometimes used to describe diamond shape?

Some people may casually use the term “cut” when the conversation may actually be about diamond shape. This is common, and although the terms have very different definitions, the words are sometimes used interchangeably for the sake of clarity.

For instance, if a retailer referred to a particular diamond as “round cut”, they are actually talking about the shape. They are referring to the fact that a gem cutter cut the rough diamond into a round shape.

Alternately, if you see “round brilliant” mentioned in a diamond’s description, this is actually a reference to its cut. “Round brilliant” is a style of cut, and it means this is a diamond that has 57 or 58 specifically cut facets with a round shape.

The terms can be very confusing when overly dissected, but just remember that shape refers to a diamond’s actual outline and cut covers the diamond's many facets and stylistic nuances.

11 popular diamond shapes—with buying tips

So what are the different types of diamond shapes, and how do they compare? Before we discuss some of the most popular shapes, let’s break down their different categories and one of their most important characteristics: the length-to-width ratio.

First, all diamond shapes fit into two categories: standard round brilliant and “fancy shapes”. Essentially, if a gem is not a round brilliant, it falls under the fancy diamond shapes name. This category includes standard shapes like square, oval, triangle, and rectangle as well as some wilder forms like marquise, pear, and heart shapes. Each of these shapes has its own personality, and choosing the right one for yourself or a loved one can be challenging!

Next, gemologists craft these shapes with specific length-to-width ratios required for optimal brilliance.🏆 The length-to-width ratio of a shape dictates its proportions, and it is expressed as the length of the diamond divided by the width. Length-to-width ratios also ensure ideal symmetry for every shape, as the suggested dimensions for each shape provide the most scintillation. While it may seem like an unimportant quality, length-to-width ratios are a great guide for understanding how balanced a particular diamond may be in relation to an ideal shape and cut.

👉🏻Here are 7 of the most popular diamond shapes:


Diamond Shape: Round

Gem cutters have crafted beautiful round diamonds since the 1700s, but the round brilliant cut we know and love today was refined in 1919 by Marcel Tolkowsky. The shape’s 57 or 58 facets accentuate the light flowing through each diamond, creating unmatched brilliance, fire, and scintillation. Those who wish to buy a round diamond should focus on its cut, and the stone’s ideal length-to-width ratio is 1.00 to 1.03.

The most popular shape of diamond sold in the world, round diamonds also make up about 50% of center stones in rings with side features. Elegant, timeless, and endlessly appealing, they are the perfect centerpiece when nestled between more traditional side stones—like square, triangle, or additional round diamonds—or bold ones with a bit of pizzazz, such as pear or baguette gems.


Diamond Shape: Square (Princess Cut)

With the ability to look traditional yet new age at the same time, square shapes have been a popular option for diamonds since their inception in the 1960s. The most common cuts for square diamonds are princess and quadrillion, and both cuts should be set in a ring or pendant setting that protects the delicate, pointed corners. Look for length-to-width ratios between 1.00 and 1.05 for perfectly square stones.

The engagement stone of Kate Bosworth and Jessica Biel, square shapes are perfect for long fingers and refined taste. For the environmentally friendly bride, square-cut diamonds are also the answer to any waste concerns. In fact, gem cutters use 80% of a rough diamond to achieve the square cut!


Oval Diamond Shape

One of the oldest known diamond cuts, oval-shaped stones were first mentioned in 1304 when referring to the dazzling Koh-I-Noor. However, the oval diamond has seen a rise in popularity over the last 10 years. A length-to-width ratio of 1.35 to 1.50 will provide you the classic oval shape, but these diamonds can be longer or shorter depending on personal preference.

Chic and trendy, oval diamonds are perfect for the bold wearer who likes to make a statement with his or her fashion choices. While oval diamonds are incredibly durable due to their lack of corners, improperly cut ones do suffer from the “bow tie” effect. This means a darker band of light runs across the center of the stone. It doesn’t happen to all oval diamonds, but just be on the lookout if you’re shopping for this style!

Bow Tie Effect of an Oval Diamond (James Allen)
Bow tie effect of an oval diamond (James Allen SKU: 10866890)


Marquise Shape Diamond

A historic shape that’s slowly becoming in style once more, marquise diamonds were made to resemble the mouth of King Louis XV’s mistress. Marquis shapes range from 1.85 to 2.00 in their most ideal length-to-width ratio, with most stones measuring at 1.75 to 2.25.

Marquise shaped diamonds are fierce, and they can make small fingers appear long and slender. Because of their royal origins, they induce feelings of refinement for an exceptional, regal look. The marquise shape is also perfect for those who prefer halo settings, as a smaller marquise diamond with a brilliant halo of smaller stones can dazzle even the toughest critics.

Marquise Cluster Halo Diamond Engagement Ring in White Gold
James Allen (SKU: 18016W14)


The most prominent cuts in this category are the emerald cut and radiant cut. Although similar, these two shapes do have some differences as outlined below.


With Art Deco style and a large, mirror-like table that glistens, emerald cut diamonds ooze luxury. You’re in good company if you prefer this style, as Beyoncé and Jennifer Lopez both sport decadent emerald-cut diamonds.

Jennifer Lopez's Octagonal Shape Emerald Cut Diamond Engagement Ring

The most popular length-to-width ratio for an octagonal diamond is 1.50, but anything between 1.30 and 1.60 would look great. The smooth corners also make it a great choice for daring settings, and it looks amazing when set as a solitaire. Just make sure you select a high clarity stone, as the large table reveals most inclusions.


Octagonal Diamond: Radiant Cut

In addition to the rectangular dimensions of the emerald cut, the radiant cut can also be square in shape. As such, the ideal length-to-width ratio can range from a perfect 1.00 to 1.30, depending on the shape you desire. The radiant shape also has a “mixed cut”: a cross between the step cut of an emerald shaped diamond and the brilliant style of round diamonds.

Radiant facets are also triangular and non-rectangular, which sets it apart from the parallel facets of the emerald cut. However, these facets are carefully crafted to provide additional brilliance. With its unique shape and a sparkle that rivals the classic round diamond, it’s ideal for anyone who wants an edgy cut with bright fire.😎


Another octagonal shape you may find is the Asscher cut. Introduced in 1902, the Asscher diamond has risen to popularity over the two decades. With a smaller table, cut corners, and more facets layered into its cut, this style is sturdy and eye-catching. The ideal length-to-width ratio for an Asscher stone is 1.00 to 1.05. 💡They’re also an affordable option for any buyers on a budget!


Diamond Shape: Pear

The engagement stone of choice for Victoria Beckham, Sophie Turner, and Jessica Simpson, pear-shaped diamonds have really come into their own in the last 20 years. With delicate, rounded shoulders and a sharp, direct point, pear shapes are both sophisticated and daring. Their ideal length-to-width ratio is 1.45 to 1.75, and they can be slender or wider depending on personal preference.

Just be careful of the diamond’s point: like any other diamond with sharp ends, they’re prone to chip if not properly set. Setting a pear stone in a rose gold or yellow gold halo setting is a great way to protect the point while creating a one of a kind look. And, similar to the oval diamond, pear shapes may also suffer from the bow tie effect, so thoroughly check your diamond of choice before buying!

Pear Diamond in Rose Gold Halo Setting
Blue Nile (Stock: 76897)


Rectangular diamonds aren’t just a four-sided stone, but rather the term refers to a variety of desirable diamond shapes. These classic gems boast parallel sides and straight corners, and they have some of the largest tables available to make smaller stones look much bigger. As with all diamonds that have larger tables, clarity is key in ensuring you can’t see any inclusions during wear.

Some common rectangular diamond shapes and cuts include:


Diamond Shape: Rectangle (Cushion Cut)

Soft and delicate like a pillow, the traditional cushion shape is perfect for those who prefer a more subtle diamond. With rounded corners and 58 facets, this stone will shine in any setting. It has a length-to-width ratio of 1.15 to 1.25.


Derived from the French word baguette, which means “long rod”, these shapes have long been used as side stones in many settings. They’re perfect for anyone who loves Art Deco flair, with 24 parallel facets, the ability to be tapered, and a length-to-width ratio of 1.50 to 2.40. They can even be included on mens’ wedding bands!

Platinum Tapered Baguette Diamond Engagement Ring
Brilliant Earth (Style: BE503TB230-PT)

😃Additionally, here are 4 other fun shapes for those who prefer a more unique style:


Heart Shape Diamond

Feminine, romantic, and a bold fashion choice, the heart-shaped diamond is beloved by vogue women like Lady Gaga and Nicki Minaj. This diamond shape requires balanced symmetry, although the width and slimness of the shape itself may vary by preference. The ideal length-to-width ratio of a heart-shaped diamond is 1.00, with lower ratios creating fuller hearts and higher ratios appearing longer.

This diamond shape’s meaning is immediately apparent, as the heart symbolizes eternal love and devotion. Heart-shaped diamonds look amazing when set as solitaires in a prong or bezel setting, and they also look wonderful in halo settings or on rose gold.


Triangle Diamond

An uncommon but historic cut, triangular diamonds first appeared in the 1500s. Triangular diamonds are cut in a brilliant style known as “trillion”, and this particular cut endlessly sparkles. It’s a provocative shape that’s rarely seen, and the ideal length-to-width ratio is 1.10.

Most of the time, these angular shapes are used as side stones to create contrast between different shaped diamonds and provide a sharp, elegant look. Because of their three prominent points, trillion diamonds should always be protected in a safe setting.


Another unusual shape, trapezoidal diamonds are a decadent option for side stones. A famous variation of this shape is the Cadillac cut, which is a five-sided, highly faceted diamond reminiscent of the Cadillac logo.

These shapes are ideal as side stones for diamonds with larger tables, such as emerald, Asscher, or cushion cut gems. Their elongated surfaces mean clarity is key in choosing the right one.


Somewhere between the trapezoid and the triangle is the epaulette shape. Although it’s technically more of a cut than a shape, this unique form is worth mentioning. It’s essentially a five-sided triangle with a step or brilliant cut, and they make exceptional side stones that can accent any center diamond beautifully.

FAQ: Crucial knowledge about diamond shapes you should not miss

Still not sure which diamond shape is right for you? Take a look at these frequently asked questions to help you decide which shape best suits your budget, size, and personal style requirements.

What are the most popular diamond shapes?

Round diamonds are, by far, the most popular diamond shape. With its long history, the round brilliant cut diamond has become the “go to” for elegant solitaire engagement rings, necklaces, earrings, and more. Square shapes, particularly the princess and quadrillion cuts, are also popular choices as they are the perfectly sparkly centerpieces in engagement jewelry.

Round Diamond Shape: The Most Popular

However, the diamond shape with the longest history is the oval shape. First recorded in 1304 and popularized in the 1960’s this shape has experienced a recent comeback and is popular in unique engagement pieces in increasingly trendy yellow or rose gold. Emerald and cushion cuts are also popular choices for those wearers who prefer a diamond with a larger table.

Other diamond shapes experiencing a resurgence in popularity include marquise and pear shaped stones. New fashion trends revitalized these uniquely shaped diamonds, and they look stunning both as solitaires and in halo settings.

While still loved by many, the least popular diamond shapes include triangles, hearts, and radiant diamonds. Though they may be used in niche pieces or as side stones, these diamonds are less popular as main stones in a setting.

Which diamond shape sparkles the most?

While all diamond shapes sparkle beautifully, the round diamond offers the most fire, scintillation, and brilliance.🥇 Because of the round brilliant cut and its 58 facets, this shape was specifically crafted to reflect as much light as possible.

However, although the round brilliant shines the brightest, there are several other shapes and cuts that produce equally gorgeous light displays. A radiant cut diamond has 70 facets, so it will sparkle from most angles. There’s also the cushion cut diamond, which is a hybrid of the round brilliant and an old world cut no longer used. Cushion cut diamonds typically cost less than round brilliant stones of similar quality, so you can get just as much sparkle for less cash!

Oval and marquise diamonds also provide more scintillation than the rest. Oval diamonds mimic round brilliants in many ways, meaning they are faceted to reflect the most light possible. Similar as well to the round brilliant, marquise diamonds have 58 facets designed for optimal light reflection.

Which diamond shape looks largest?

As a rule of thumb, the longer a diamond shape’s table, the larger the diamond will appear. Any shape with an elongated profile tends to look much larger than round or square counterparts of equal carat.

Emerald diamonds are the best example of this size difference. So much of an emerald diamond’s weight and mass is present in its very visible table, which makes it look much longer and larger. Trillion cut diamonds also have larger tables that appear bigger.

Which Diamond Shape Looks Largest?

Because oval, pear, and marquise diamonds have a longer profile, they tend to look larger as well. Out of these options, the marquise shape generally has the longest appearance, as the delicate points at both ends visually elongate and stretch both the stone itself and the finger on which it sits. In fact, their extended length can even make fingers look longer and slimmer!🤚🏻

The diamond shapes with the smallest profiles include princess, cushion, and Asscher. These shapes suffer from a small diameter and surface area as a result of their similar length-to-width ratios. However, that does not mean they aren’t equally beautiful!

What are the most expensive diamond shapes?

The most expensive diamond shape is typically the round brilliant. Accounting for approximately 75% of diamonds sold, round brilliants are in high demand at all times and are designed for the ultimate sparkle. As such, these stones tend to warrant a higher price tag.

Diamond Shape Price by Carat, G Color VS2
Diamond Shape Price by Carat, G Color VS2
Chart: The International Gem Society (IGS)

Marquise, oval, and heart shaped diamonds can also range into higher priced territory. Because these are also specialty cuts designed for as much scintillation as possible, they are also a bit pricier. Marquise and oval shapes are also experiencing increased popularity, which can drive their price up significantly.📈

Much of diamond cost also comes down to how much of the original rough diamond is still present in the final design. For round brilliant stones, only about 40% of the original diamond makes the cut. Diamond shapes that maintain the most of the original diamond tend to sell for lower prices, as they require less diamond waste. These more affordable shapes include emerald, Asscher, cushion, radiant, and princess cut diamonds.

Diamond shape: An extension of your personality

Diamonds come in all shapes and sizes, and it’s important to choose one that fits your personal style. From the edgy, bold look of heart, pear, or marquise shaped stones to the timeless beauty of emerald, square, and round diamonds, a diamond’s true beauty reveals itself when worn by the right person.

Don’t forget to accessorize your stone to bring out its fire as much as possible.

Consider switching up the metal of your piece’s setting, or try side stones or a halo setting to add further glam. Colored stones are also always a great option, as they can provide more depth to the white sheen of diamonds.

As mentioned, shape and cut are entirely different characteristics of a diamond that both play into its sparkle. Consider reading our article on diamond cut to gain further understanding of how these two crucial factors come together to make a diamond scintillate.

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