Emerald Square Cut Amethyst: the largest face for its weight of the cuts on these pages

Brilliance 61 · Fire 40 · Scintillation 72 · in our census, where the T73 scores 72 · 36 · 80 in amethyst

A square step cut with an open table: in quartz it shows the largest face for its weight of the cuts on our amethyst pages, and every band of colour inside.

See it in the simulatorGet the files
The Emerald Square Cut in amethyst, rendered at an angle in our 3D Gemstone Simulator under studio light
Rendered in our 3D Gemstone Simulator from the Emerald Square Cut model, 1.00 ct, studio light.

Emerald Square Cut Amethyst

The emerald square puts concentric steps on a square with cropped corners, with a shallower, more open table than the Asscher. Ours is a plain plan of 49 facets: steps falling at 28.16° on the pavilion, 61.0% from table to culet.

That open table is a window: an amethyst's colour zoning, if it has any, shows plainly through it. Rough for a step cut is worth choosing for even colour.

Against the same cut in diamond, the light falls only a little, 64 to 61; it is fire that drops.

Is an emerald square cut good for amethyst? Pros and cons

Pros

Cons

Compared with the T73 Round Brilliant in amethyst 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 amethyst (white) against the T73 Round Brilliant in amethyst (dashed): solid white where it reaches further, hatched where it falls short. Each pro and con is explained, with pictures, below.

Performance wheel: Emerald Square Cut in amethyst, against the T73 Round Brilliant in amethyst as an outline. Solid white marks where it reaches further, hatching where it falls short. The scores are listed below.50100Global−5Brilliance−11Fire+4Scintillation−8Spread+8Symmetry0Shape-norm+3Tilt−2

Against the T73 Round Brilliant in amethyst: ahead on 3, level on 1, behind on 4.

  • Global65, the comparison 70, difference −5
  • Brilliance61, the comparison 72, difference −11
  • Fire40, the comparison 36, difference +4
  • Scintillation72, the comparison 80, difference −8
  • Spread108, the comparison 100, difference +8
  • Symmetry100, the comparison 100, difference 0
  • Shape-norm80, the comparison 77, difference +3
  • Tilt78, the comparison 80, difference −2
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 amethyst gains in an emerald square

Lighter than diamond

1.10 ct at 6.5 mm, against 1.46 ct for the same cut in diamond (−25%)

6.5 mm across, the emerald square weighs 1.10 ct in amethyst and 1.46 ct in diamond: one of the heavier cuts here for its width, which quartz's lower density offsets.

Amethyst1.10 ctDiamond1.46 ct
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

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

At the same carat weight it shows more face than the T73, and more than any other cut on these amethyst pages.

Emerald Square Cut · 6.31 mm at 1.00 ct · Spread 108

T73 Round Brilliant · 7.12 mm at 1.00 ct · Spread 100

Both stones weigh 1.00 ct in amethyst 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 amethyst

Under half the diamond's fire

Fire 40 against 84 for the Emerald Square Cut in diamond: 44 points lower

Broad step facets split light into large flashes, and quartz gives them little colour. The diamond version scores 84.

Emerald square cut in amethyst face-up under a single bright light: a render from our simulator, its coloured flashes are the fire (score 40)

Emerald Square Cut in amethyst · Fire 40

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)

Emerald Square Cut in diamond · Fire 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.

What helps: The Asscher Cut Amethyst reaches 52 in a square step cut; the Oval Cut Amethyst 69.

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

More leakage than in diamond

Leakage 36 against 17 for the Emerald Square Cut in diamond: 19 points higher

36% of the light in our census leaves through the pavilion, 17% in diamond. That is a little less than the Asscher loses in amethyst.

Emerald Square Cut in amethyst · Leakage 36

Emerald square cut in amethyst tilted 0 degrees: Light Return map, 25% of the face leaking0° · 25% leak
Emerald square cut in amethyst tilted 10 degrees: Light Return map, 36% of the face leaking10° · 36% leak
Emerald square cut in amethyst tilted 20 degrees: Light Return map, 43% of the face leaking20° · 43% leak
Emerald square cut in amethyst tilted 30 degrees: Light Return map, 48% of the face leaking30° · 48% leak

Emerald Square Cut in diamond · Leakage 17

Emerald square cut in diamond tilted 0 degrees: Light Return map, 20% of the face leaking0° · 20% leak
Emerald square cut in diamond tilted 10 degrees: Light Return map, 27% of the face leaking10° · 27% leak
Emerald square cut in diamond tilted 20 degrees: Light Return map, 28% of the face leaking20° · 28% leak
Emerald square cut in diamond tilted 30 degrees: Light Return map, 28% of the face leaking30° · 28% leak
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: The Square Cut Amethyst brilliant leaks 29% in amethyst.

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

Less light than the T73

Brilliance 61 against 72 for the T73 Round Brilliant in amethyst: 11 points lower

The step pavilion at 28.16° sits far below the angles a round needs in quartz, and less of the face sends light back.

Emerald square cut in amethyst face-up Light Return map: red, green and blue show where the light returns from, grey shows where it leaks (Brilliance 61)

Emerald Square Cut in amethyst · Brilliance 61

T73 round brilliant in amethyst face-up Light Return map: red, green and blue show where the light returns from, grey shows where it leaks (Brilliance 72)

T73 Round Brilliant in amethyst · Brilliance 72

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: In a square outline, the Cushion Cut Amethyst returns 69.

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

Fewer flashes than a round

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

49 facets against the T73's 73: fewer, larger steps, and a calmer face.

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.

What helps: The Cushion Cut Amethyst scores 85 on a square outline.

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

Who an emerald square amethyst suits

Choose the emerald square for an architectural amethyst centre stone or earrings, cut from rough with even colour, where face-up size counts.

It is one of the quicker plans on these pages to cut, with 49 facets, which suits a hobby cutter's large, clean piece of amethyst.

For a step cut with more fire, the Asscher Cut Amethyst; for more light in a square, the Cushion Cut Amethyst.

Emerald Square Cut Amethyst: questions

Is an emerald square cut good for amethyst?

For face-up size, yes: Spread 108, the highest on our amethyst pages. For light, Brilliance 61 against 72 for the T73.

Emerald square or Asscher amethyst?

The emerald square leaks less (36% against 39%) and faces up a little larger; the Asscher has more fire (52 against 40).

Will colour bands show in an emerald square amethyst?

Likely, if the rough has them: the open table looks straight into the stone. Our census does not measure colour.

What does a 6.5 mm emerald square amethyst weigh?

1.10 ct, against 1.46 ct 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

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

Other cuts in amethyst

The Emerald Square Cut in other gemstones