A diamond shape is the outline of a diamond seen from above: round, oval, princess, cushion, emerald, pear, marquise, radiant, Asscher or heart. Round (26%) and oval (25%) were the top center-stone shapes in The Knot Real Weddings Study 2026, while cut grades facet proportions and polish, not the outline.
Diamond Shapes Chart: 10 Shapes Compared
The chart below compares the 10 standard diamond shapes on faceting style, facet count, popular length-to-width ratio, bow-tie risk and price per carat versus round.
| Shape | Faceting style | Typical facets | Popular L/W ratio | Bow-tie | Price per carat vs. round | Buying tip |
|---|---|---|---|---|---|---|
| Round | Brilliant | 57-58 | 1.00-1.03 | No | Highest | Hides small inclusions; VS2-SI1 can look clean |
| Oval | Brilliant | 56-58 | 1.30-1.50 | Yes | Lower | Check the bow-tie in person |
| Princess | Modified brilliant | 58-76 | 1.00-1.05 | No | Lower | Protect corners with V-prongs |
| Cushion | Modified brilliant | 58-64 | 1.00-1.05 square, 1.15-1.30 elongated | Rare | Lower | Facet style varies: "chunky" or "crushed ice" |
| Emerald | Step | 57 | 1.30-1.50 | No | Among the lowest | Prioritize clarity |
| Pear | Brilliant | 56-58 | 1.45-1.75 | Yes | Lower | Protect the point with a V-prong |
| Marquise | Brilliant | 56-58 | 1.75-2.25 | Yes | Lower | Largest look per carat |
| Radiant | Modified brilliant | 70 | 1.00-1.05 square, 1.20+ rectangular | Rare | Lower | Hides inclusions better than emerald |
| Asscher | Step | 58-74 | 1.00-1.05 | No | Among the lowest | Prioritize clarity |
| Heart | Brilliant | 56-58 | 0.90-1.10 | Can show | Lower | Needs symmetry; bezel or 3-prong suits small sizes |
The L/W ranges in this chart are common market preferences, not GIA grading rules.
Diamond Shape vs Diamond Cut
Shape is the geometric outline of a diamond viewed from above. Cut is different. It describes how well the facets are proportioned, aligned and polished, and it controls how the stone handles light as one of the 4Cs. GIA gives an overall cut grade only to standard round brilliants; fancy shapes receive polish and symmetry grades instead. "Fancy shape" means any shape other than round.
The word "cut" carries three meanings in jewelry. It names shapes, as in "emerald cut", it names faceting styles like brilliant cut and step cut, and it names the 4Cs quality grade.
Brilliant, Step and Modified Brilliant Faceting
Brilliant faceting uses triangular and kite-shaped facets radiating from the center; round, oval, pear, marquise and heart diamonds use it. Step faceting is different. Long parallel rectangular facets create a "hall of mirrors" look, and emerald, Asscher and baguette cuts use it. Modified brilliants put brilliant facets on a square or rectangular outline, which covers princess, radiant and cushion. A GIA report describes a princess cut as a "square modified brilliant".
Every faceted diamond shares the same basic anatomy:
| Part | What it is |
|---|---|
| Table | Largest top facet |
| Crown | Upper part above girdle |
| Girdle | Outer edge of stone |
| Pavilion | Lower part below girdle |
| Culet | Bottom point or facet |
The 10 Standard Diamond Shapes
The 10 standard shapes, in the order used above, are round, oval, princess, cushion, emerald, pear, marquise, radiant, Asscher and heart.
Round Brilliant
The round brilliant has 57 or 58 facets, with 58 counting the culet. Marcel Tolkowsky published proportions for maximum brilliance in 1919 in "Diamond Design", and those proportions still anchor modern cutting. Round is the only shape that receives a GIA cut grade. It also carries the highest price per carat, because more rough is lost in cutting and demand is highest. Our round brilliant cut guide covers grading in detail.
Oval
The oval is an elongated brilliant with 56-58 facets and a popular length-to-width ratio of 1.30-1.50. Its spread makes it look larger than a round of the same carat weight. Most ovals show some bow-tie, a darker band across the center. Ovals were rarely seen until the mid-1900s. Yet The Knot Real Weddings Study 2026 puts oval at 25% of engagement ring center stones.
Princess
The princess has a square outline with pointed corners and 58-76 facets, often 76. GIA reports name it a "square modified brilliant". The corners can chip. V-prongs are the standard protection, and princess costs less per carat than round while its brilliance hides small inclusions well.
Cushion
The cushion is square or rectangular with rounded corners and 58-64 facets. It descends from the old mine cut, developed in 18th-century Europe. Facet style varies. Some cushions show a "chunky" look, others a "crushed ice" look. Warmer color grades, G to J on the GIA scale, reduce the price further.
Emerald
The emerald cut is a rectangular step cut with cropped corners and 57 facets. Its large open table shows inclusions easily, so clarity matters more here than in brilliant shapes. The popular ratio runs 1.30-1.50. Emerald ranks among the least expensive shapes per carat.
Pear
The pear is a teardrop with one rounded end and one point, cut with 56-58 facets. The popular ratio is 1.45-1.75, and a bow-tie can appear across the center. Most wearers point the tip toward the fingertip to elongate the finger. The pear cut first appeared more than 500 years ago.
Marquise
The marquise is a boat shape with two points and 56-58 facets, at a popular ratio of 1.75-2.25. It is the largest-looking shape per carat. According to legend, King Louis XV of France commissioned the shape to match the smile of the Marquise de Pompadour. Both points need prong protection. See our marquise cut engagement ring guide for settings.
Radiant
The radiant is a cut-cornered square or rectangle with brilliant faceting and 70 facets. Henry Grossbard created it in 1977. The dense facet pattern hides inclusions better than emerald and Asscher step cuts.
Asscher
The Asscher is a square step cut with cropped corners, developed in 1902 by the Asscher brothers of Amsterdam, Holland. It has a higher crown and smaller table than an emerald cut, and its concentric squares produce a "windmill" look. Facet counts run 58-74; modern versions reach 74. Like emerald, it rewards higher clarity.
Heart
The heart has 56-58 facets and is the hardest shape to cut symmetrically, because both lobes must match. Small hearts are often set in bezel or three-prong settings to protect the point.
Length-to-Width Ratio and the Bow-Tie Effect
Length-to-width ratio is the length divided by the width; a 7.0 x 5.0 mm oval has a ratio of 1.40. A ratio of 1.00 means the stone is perfectly square or round. Popular ranges for elongated shapes run from 1.20 to 2.00 depending on the shape. No stone is mathematically perfect. Krikawa notes a round can measure 6.5 x 6.55 mm, slightly off-round. Square shapes like princess, Asscher and radiant look best near 1:1, especially when kite-set on a diagonal.
The bow-tie effect is a darker band across the center of ovals, pears and marquises, and some hearts, caused by facet placement. Its strength depends on cut quality. No grade on a report measures it. View the stone in person or on video to judge it.
Orientation changes the effect of any elongated shape. A north-south setting runs the long axis along the finger and elongates it; an east-west setting runs the long axis across the finger and can make it look wider.
Most Popular, Biggest-Looking and Least Expensive Shapes
The Knot Real Weddings Study 2026 covered couples married in 2025. It found round at 26% and oval at 25% of engagement ring center stones. Emerald, princess, pear and marquise came in at 8% each.
Marquise, oval and pear show the largest face-up area per carat, an effect jewelers call spread. Our diamond size chart shows millimeter measurements versus carat weight for each shape.
Round is the most expensive shape per carat because demand is highest and more rough is lost in cutting. Emerald and Asscher are typically the least expensive per carat, and oval and cushion also price below round. One caveat: step cuts may need a higher clarity grade, which offsets part of the saving.
Rare and Antique Diamond Shapes
Beyond the 10 standard shapes, less common shapes are mostly used as accent stones or in antique jewelry.
| Shape | Outline and faceting | Typical use |
|---|---|---|
| Trillion | Triangle, brilliant facets, pointed or rounded corners | Side stones, some center stones |
| Baguette | Narrow rectangle, step facets | Accent stones, bands |
| Tapered baguette | Rectangle narrowing at one end, step facets | Side stones beside a center stone |
| Kite | Four-sided kite outline | Accents, modern designs |
| Shield | Shield outline, brilliant or step facets | Side stones |
| Hexagon | Six-sided, step facets | Modern center and fashion stones |
| Old mine | Cushion-like, small table, high crown, large culet | Antique jewelry (18th-19th century) |
| Old European | Round, small table, high crown, open culet | Antique round, predecessor of the modern round brilliant |
| Rose cut | Flat bottom, domed top of triangular facets | Antique and vintage-style jewelry |
| Briolette | Teardrop faceted all around, no table | Pendants and drop earrings |
Old mine and old European originals are scarce because they were hand-cut before modern proportions existed, and supply is limited to surviving antique stones and recuts. "Kite" also names a diagonal setting style, not only a shape. Billig's lab-grown collection includes hexagon-cut pieces.
How to Choose a Diamond Shape for an Engagement Ring
Hand and Finger
Elongated shapes like oval, pear, marquise and emerald, set north-south, make fingers look longer. Wide east-west settings make fingers look wider. A narrow band helps either way.
Lifestyle and Setting
Pointed shapes like princess, pear, marquise and heart need V-prongs or a bezel; a bezel protects the edges all around. Rounded outlines like round, oval and cushion have no points to chip. At Billig, the free prong check while you wait applies to any shape.
Clarity and Color Budget
Brilliant shapes like round, princess, cushion and radiant hide small inclusions, while step cuts like emerald and Asscher need higher clarity; our diamond clarity scale guide explains the grades. Elongated brilliants can show warmer color at the ends. Check the GIA color scale before choosing a grade.
Natural or Lab-Grown
Shape options are identical for natural and lab-grown diamonds; our lab-grown vs natural diamond guide compares the two. Billig's build-a-ring tool starts with a loose GIA- or IGI-graded diamond, then a setting.
Diamond Shapes FAQ
What are the different diamond shapes called?
The 10 standard shapes are round, oval, princess, cushion, emerald, pear, marquise, radiant, Asscher and heart. Rarer shapes include trillion, baguette, kite, shield, old mine, old European and rose cut.
What is the most popular engagement ring shape in 2026?
Round is the most chosen shape at 26% of center stones, with oval close behind at 25%. The figures come from The Knot Real Weddings Study 2026, which surveyed couples married in 2025.
Which diamond shape looks the biggest?
Marquise looks the biggest per carat, followed by oval and pear. Their elongated outlines give them more face-up surface area, or spread, than other shapes of the same weight.
What is the most expensive diamond shape, and the least expensive?
Round is the most expensive shape per carat because of high demand and greater rough loss in cutting. Emerald and Asscher are typically the least expensive per carat.
Which diamond shape sparkles the most?
The round brilliant sparkles the most, with 57-58 facets arranged on Tolkowsky's 1919 proportions. Among square shapes, radiant and princess produce the most sparkle.
What is the long diamond shape called?
The longest diamond shape is the marquise, at a popular ratio of 1.75-2.25. Oval and pear are also elongated shapes.
What is the rectangle diamond shape called?
The rectangular step cut is the emerald cut, while the rectangular brilliant is the radiant. Elongated cushions and small baguette accents are also rectangular.
What are the rarest diamond shapes?
The rarest shapes are antique old mine and old European originals, plus kite and shield cuts. Rarity here means limited supply, not automatically a higher price.