Emerald Square Cut Emerald: Pros, Cons & Spread

The emerald step cut takes its name from the stone, and the site's gemstone notes say emeralds get step cuts for their colour, their inclusions and some brittleness. This is the square version, with cropped corners, concentric steps and an open table. In our model the steps add up to 49 facets, the pavilion figure is a low 28.16° and the total depth 61.0%.

What do the numbers say? This square step cut is in emerald's top ten among the jewelry cuts, and so is the Asscher, but the classic rectangular Emerald Cut is not: it returns 58. Every step cut we measure in emerald trails the T73's 78 on light. The reasons for the tradition are practical and about colour, and our census measures neither.

Does emerald suit the Emerald Square cut? Pros and cons

Pros

Lighter than the diamond version 1.13 vs 1.46 ct
The largest face for its weight on our emerald pages 108 vs 100

Cons

Much less fire than in diamond 46 vs 84
A third of the light leaks 32 vs 17
Less light than a round 66 vs 78
Fewer, broader flashes than a round 72 vs 80

Compared with the T73 Round Brilliant in emerald and with the Emerald Square Cut in diamond. A difference counts from 3 points (Brilliance, Fire, Tilt, Leakage), 5 (Scintillation, Symmetry), 2 (Spread) or 5% (weight); Tilt counts as a pro only for a stone within 5 points of the brilliance it is compared with. How we measure.

All eight scores against the T73

At a glance: the Emerald Square Cut in emerald (white) against the T73 Round Brilliant in emerald (dashed): solid white where it reaches further, hatched where it falls short. Each pro and con is explained, with pictures, below.

Against the T73 Round Brilliant in emerald: ahead on 3, level on 2, behind on 3.

Global68, the comparison 73, difference −5
Brilliance66, the comparison 78, difference −12
Fire46, the comparison 39, difference +7
Scintillation72, the comparison 80, difference −8
Spread108, the comparison 100, difference +8
Symmetry100, the comparison 100, difference 0
Shape-norm87, the comparison 84, difference +3
Tilt77, the comparison 77, difference 0

Face-up light census, a different measure from the Cut Grading Tool; Spread and Shape-norm above 100 sit on the ring.

Open it in the Cut Performance Wheel

What emerald gains in an Emerald Square cut

Lighter than the diamond version

1.13 ct at 6.5 mm, against 1.46 ct for the same cut in diamond (−23%)

At 6.5 mm across the stone is 1.13 ct in emerald and 1.46 ct in diamond; beryl's specific gravity, 2.72, is the reason.

A Emerald Square Cut 6.5 mm across, weighed from the model's measured volume and each stone's specific gravity.

Try it yourself: Weights in all seven gemstones on the Emerald Square Cut page

The largest face for its weight on our emerald pages

Spread 108 against 100 for the T73 Round Brilliant in emerald: 8 points higher

Spread 108 against 100 for the T73. A shallow pavilion keeps weight out of the bottom of the stone, so each carat shows more surface.

Emerald Square Cut · 6.25 mm at 1.00 ct · Spread 108

T73 Round Brilliant · 7.06 mm at 1.00 ct · Spread 100

Both stones weigh 1.00 ct in emerald and are drawn to the same scale, from each cut's own model. Spread is face-up size per carat: a deeper stone carries more weight below the girdle and looks smaller for its weight.

Try it yourself: Compare the Spread spoke in the Cut Performance Wheel

The catch with an Emerald Square emerald

Much less fire than in diamond

Fire 46 against 84 for the Emerald Square Cut in diamond: 38 points lower

Fire 46 against 84, though above the T73 in emerald (39). Step cuts show emerald's colour in broad planes rather than in spectral flashes.

Emerald square cut in emerald face-up under a single bright light: a render from our simulator, its coloured flashes are the fire (score 46) — Look at the coloured flashes: those are fire. Same light, same size, same face-up angle; rendered by our 3D Gemstone Simulator from each cut's own model.

Emerald square cut in diamond face-up under a single bright light: a render from our simulator, its coloured flashes are the fire (score 84) — Look at the coloured flashes: those are fire. Same light, same size, same face-up angle; rendered by our 3D Gemstone Simulator from each cut's own model.

Try it yourself: See the fire in the 3D Gemstone Simulator

A third of the light leaks

Leakage 32 against 17 for the Emerald Square Cut in diamond: 15 points higher

32% in our census, about twice the diamond version's 17%. The steps run at a pavilion figure of 28.16°, far below emerald's critical angle of 39.4°.

Emerald square cut in emerald tilted 0 degrees: Light Return map, 25% of the face leaking — Each frame is the Light Return map with the stone tilted away from you by the angle shown; grey is light leaving through the pavilion. The share under each frame is that picture's own.

Emerald square cut in emerald tilted 10 degrees: Light Return map, 34% of the face leaking — Each frame is the Light Return map with the stone tilted away from you by the angle shown; grey is light leaving through the pavilion. The share under each frame is that picture's own.

What helps: We have not measured a steeper step cut, so we make no promise for one. The Square Cut Emerald brilliant leaks 26%.

Try it yourself: Tilt it yourself in the simulator's light map

Less light than a round

Brilliance 66 against 78 for the T73 Round Brilliant in emerald: 12 points lower

66 against 78. Here emerald is not the problem: the same cut in diamond returns 64, slightly less.

Emerald square cut in emerald face-up Light Return map: red, green and blue show where the light returns from, grey shows where it leaks (Brilliance 66) — Red, green and blue = light returning to the eye; grey = light leaving through the pavilion. This is the head-on view; the Brilliance score averages a wider cone of light, so the score can differ from what one picture shows.

T73 round brilliant in emerald face-up Light Return map: red, green and blue show where the light returns from, grey shows where it leaks (Brilliance 78) — Red, green and blue = light returning to the eye; grey = light leaving through the pavilion. This is the head-on view; the Brilliance score averages a wider cone of light, so the score can differ from what one picture shows.

What helps: For a square outline with more light, the Square Cut Emerald brilliant returns 68, the Cushion Cut Emerald 74.

Try it yourself: Open this Light Return map in the simulator

Fewer, broader flashes than a round

Scintillation 72 against 80 for the T73 Round Brilliant in emerald: 8 points lower

49 facets in concentric steps against the T73's 73 give scintillation 72. The step cut's flashes are larger and slower, in any stone.

Emerald Square Cut · 49 facets · Scintillation 72

T73 Round Brilliant · 73 facets · Scintillation 80

Scintillation follows the number of facets: more facets, more and smaller flashes as the stone moves. Count the facets in each crown. Drawn from each cut's own model.

Try it yourself: Compare the Scintillation spoke in the Cut Performance Wheel

Who an Emerald Square emerald suits

Choose the Emerald Square for a traditional step-cut emerald with an open table, where the colour and a large face for the weight matter more than light. Of the step cuts on our emerald pages it returns the most light.

For more light in a square, the Cushion Cut Emerald or Square Cut Emerald. For a deeper-cornered step cut, the Asscher Cut Emerald.

Emerald Square Cut Emerald: questions

Does the emerald cut suit emerald best?

Not on light. This square step cut returns 66 and the rectangular Emerald Cut 58, against 90 for DG-M5. Its strengths are a large face for the weight and the traditional look.

Emerald Square or Asscher for an emerald?

This one: more light (66 against 62), less leakage (32% against 37%) and a slightly larger face. The Asscher scores more fire.

How much light does an Emerald Square emerald leak?

32% in our census, against 22% for the T73 in emerald and 17% for the same cut in diamond.

Get the Emerald Square Cut files

6 formatsMillimetresWatertight

Emerald Square Cut 3D files

The Emerald Square Cut as exact geometry: 49 planar facets, real-world scale, ready for CAD, rendering, printing and casting.

STEPExact faceted solid for CAD
3DMRhino, closed mesh on its own layer
STLWatertight mesh for printing and casting
OBJMesh for modelling and rendering
FBXBlender, 3ds Max, Maya, Cinema 4D, Unity, Unreal
GLBWeb, AR and quick previews

€9.99 · Personal useBuy the 3D files

GemCad96 index

Emerald Square Cut cutting files

The Emerald Square Cut as a faceting design: 41 + 8 girdles = 49 facets, 96 index, 4-fold symmetry, ready for the machine.

.ascGemCad design file, 96 index gear
.csvTier table: angles, indices and cutting order
DiagramPrintable faceting diagram

€9.99 · Personal useBuy the cutting files

Questions before you buy? Email us.

More gemstones and cuts

Emerald: optical properties and the top ten cuts · The Emerald Square Cut: specifications, model and files

Emerald Square Cut Emerald: the widest face for its weight of any cut on these pages