Diamond Shapes Chart: Every Shape Compared Side by Side

A complete diamond shapes chart puts every outline on the same page and compares them on the variables that change a decision. Not history, not romance. Face up size, price position, sparkle behaviour, what the shape does to the finger, and what it needs to survive daily wear. The outlines below are drawn at the length to width proportions each shape is normally cut to.

The full chart is below. Read the face up size column first, because it is the one buyers are most often surprised by, then the price column, then the durability column if the piece is going to be worn every day.

The narrative version of this material, shape family by shape family, is in the lab diamond shapes guide for 2026. This page is the reference chart. Use whichever suits how you are shopping.

Marquise looks the biggest per carat, followed by pear, oval, trillion and emerald. Princess, asscher and cushion look the smallest for the same weight. The reason is geometry, not grading.

A carat is a unit of weight. Where a cutter puts that weight is a design choice. Deep shapes such as princess and asscher carry a large share of the weight in the pavilion, below the girdle, where nobody sees it. Elongated and shallow shapes such as marquise, pear and trillion spread the same weight across the table, so more of it faces up. Two stones at 2.00 carats with identical IGI grades can differ visibly on the hand for this reason alone.

Practical consequence: if maximum visual size for the budget is the goal, an elongated fancy shape delivers it. If the goal is the classic silhouette, round is round and nothing substitutes for it. Carat by carat pricing across the market is broken down in the lab diamond price per carat analysis for 2026.

In the loose stone market, yes. Round commands the highest price per carat of any shape. Elongated fancy shapes generally cost less per carat at the same colour, clarity and weight. Two forces drive it: round wastes the most rough during cutting, and round carries the strongest standing demand.

The market baseline for lab grown loose stones, before shape premium, is published monthly. StoneAlgo recorded these averages in May 2026:

Those are market averages across shapes, not shape specific quotes. Anyone publishing a precise premium for heart versus cushion is estimating. What can be published precisely is a finished catalog, because those prices are listed and verifiable. Across Draco's 5 carat tennis bracelets, four different shapes carry the same list price.

Round, oval, emerald and pear are all listed at 2,720 CAD in the 5 carat tennis bracelet. The heart and the mixed baguette and round designs sit at 2,999 CAD, and the difference there is construction complexity, not the shape premium of the stones. The lesson is that in a finished piece, shape premium is often absorbed by the setting, the labour and the retailer's structure long before it reaches the price tag.

Shapes split into two faceting families, and they behave in completely different ways under light. Brilliant cuts scatter. Step cuts reflect.

Brilliant cuts include round, oval, pear, marquise, heart, cushion, princess and radiant. Their facets are triangular and kite shaped, arranged to bounce light back at the eye as small rapid flashes. This is the pattern most people mean by sparkle. Elongated brilliants can show a bow tie, a dark band across the centre caused by the wearer's own shadow. A well cut oval or pear minimises it. It never disappears entirely, and a stone photographed only from a distance may be hiding one.

Step cuts include emerald, asscher and baguette. Their facets run as long parallel planes to the girdle, producing a hall of mirrors effect: fewer flashes, but wider and more architectural. The trade off is honesty. A step cut has an open table and almost no ability to hide an inclusion, so clarity matters more here than in any brilliant cut. Every Draco stone is IGI certified at VS2 and better, which is the grade band where step cuts stay eye clean.

Trillion sits between the two, cut shallow with broad open flashes, which is why it appears more often as a side stone than a centre.

Marquise, oval, pear, emerald and elongated radiant lengthen the finger. Round, princess, asscher and square cushion do not. The rule is simple: any shape cut above roughly 1.30 length to width, and set with the long axis running up the finger, elongates.

Two details decide whether the effect actually lands. The first is orientation. A pear or oval set east to west, across the finger, reverses the effect and widens instead. The second is ratio. Ratios sit on a spectrum, and a 1.30 oval reads close to round while a 1.50 oval reads clearly elongated. If lengthening is the point, buy toward the upper end of the range and confirm the millimetre measurements on the IGI report rather than trusting a photograph.

Baguettes lengthen differently. A single baguette is small, but a row of them set in a channel draws a continuous line along the finger, which is why they appear in bands rather than as solitaires.

Marquise, pear, heart and trillion carry points. Princess and baguette carry sharp ninety degree corners. Those are the six shapes where the setting is not decoration, it is structural.

Diamond is Mohs 10 and the hardest material in daily use, but hardness is resistance to scratching, not resistance to a sharp knock. A point or an exposed corner concentrates force on very little material. That is where damage happens, and it is entirely preventable in the setting.

Once the shape is settled, the rest of the decision is grades, metal and budget. That sequence is laid out in the guide to choosing a lab diamond engagement ring, and any of these shapes can be specified from scratch in the Draco ring builder.