DG-Octagonal Kite Amethyst: an eight-fold kite pattern, a quarter lighter than diamond

Brilliance 50 · Fire 33 · Scintillation 60 · in our census, where the T73 scores 72 · 36 · 80 in amethyst

In diamond this kite pattern leaks very little light. In quartz half of it leaves through the back, though the pavilion still clears the critical angle.

See it in the simulatorGet the files
The DG-Octagonal Kite in amethyst, rendered at an angle in our 3D Gemstone Simulator under studio light
Rendered in our 3D Gemstone Simulator from the DG-Octagonal Kite model, 1.00 ct, studio light.

DG-Octagonal Kite Amethyst

DG-Octagonal Kite is an eight-fold cut with a large octagonal table: kites run from the girdle corners to the table, triangles sit on the girdle flats, and long pavilion kites close to a point. Our model has 41 facets, a 55.0% table, a 32.0° crown, a 43.0° pavilion and 70.0% depth.

It was drawn for emerald, with pavilion kites that stand clear of emerald's critical angle. At 43.0° they also clear amethyst's 40.4°. The census still loses half the light in amethyst; we read that as head-on light reflecting once from the kites and then lost at a second facet.

Against the same kite in diamond the losses are large: a little under three fifths of the light and about two fifths of the fire survive the change of stone.

Does DG-Octagonal Kite work in amethyst? Pros and cons

Pros

Cons

Compared with the T73 Round Brilliant in amethyst and with the DG-Octagonal Kite in diamond. A difference counts from 3 points (Brilliance, Fire, Tilt, Leakage), 5 (Scintillation, Symmetry), 4% (face-up size per carat) 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 DG-Octagonal Kite 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: DG-Octagonal Kite 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−10Brilliance−22Fire−3Scintillation−20Spread−4Symmetry0Shape-norm−19Tilt+20

Against the T73 Round Brilliant in amethyst: ahead on 1, level on 1, behind on 6.

  • Global60, the comparison 70, difference −10
  • Brilliance50, the comparison 72, difference −22
  • Fire33, the comparison 36, difference −3
  • Scintillation60, the comparison 80, difference −20
  • Spread96, the comparison 100, difference −4
  • Symmetry100, the comparison 100, difference 0
  • Shape-norm58, the comparison 77, difference −19
  • Tilt100, the comparison 80, difference +20
Face-up light census, a different measure from the Cut Grading Tool; Spread and Shape-norm above 100 sit on the ring. Spread is the census's estimate from depth alone; the face-up size in the pros and cons is measured from each model's outline.
Open it in the Cut Performance Wheel

What amethyst gains in DG-Octagonal Kite

A quarter lighter than diamond

0.94 ct at 6.5 mm, against 1.25 ct for the same cut in diamond (−25%)

With 70.0% depth this is a tall stone for its width, and amethyst's specific gravity of 2.65 keeps it a quarter lighter than diamond's 3.52 would.

Amethyst0.94 ctDiamond1.25 ct
A DG-Octagonal Kite 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 DG-Octagonal Kite page

DG-Octagonal Kite's costs in amethyst

Two fifths of the diamond's fire

Fire 33 against 82 for the DG-Octagonal Kite in diamond: 49 points lower

The kite scores 82 for fire in diamond and 33 in quartz. In amethyst it also sits a few points under the T73.

Dg-octagonal kite in amethyst face-up under a single bright light: a render from our simulator, its coloured flashes are the fire (score 33)

DG-Octagonal Kite in amethyst · Fire 33

Dg-octagonal kite in diamond face-up under a single bright light: a render from our simulator, its coloured flashes are the fire (score 82)

DG-Octagonal Kite in diamond · Fire 82

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: Among amethyst cuts within ten points of the T73's brilliance, DG-Anteros Amethyst has the highest fire, 54; DG-M5 Amethyst, brighter still, scores 50.

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

Half the light leaks

Leakage 50 against 7 for the DG-Octagonal Kite in diamond: 43 points higher

In the picture, the diamond's strip is almost clear face-up and still under a quarter grey in its last frame. In amethyst the census loses half the light through the pavilion.

DG-Octagonal Kite in amethyst · Leakage 50

Dg-octagonal kite in amethyst tilted 0 degrees: Light Return map, 57% of the face leaking0° · 57% leak
Dg-octagonal kite in amethyst tilted 10 degrees: Light Return map, 44% of the face leaking10° · 44% leak
Dg-octagonal kite in amethyst tilted 20 degrees: Light Return map, 49% of the face leaking20° · 49% leak
Dg-octagonal kite in amethyst tilted 30 degrees: Light Return map, 58% of the face leaking30° · 58% leak

DG-Octagonal Kite in diamond · Leakage 7

Dg-octagonal kite in diamond tilted 0 degrees: Light Return map, 3% of the face leaking0° · 3% leak
Dg-octagonal kite in diamond tilted 10 degrees: Light Return map, 6% of the face leaking10° · 6% leak
Dg-octagonal kite in diamond tilted 20 degrees: Light Return map, 18% of the face leaking20° · 18% leak
Dg-octagonal kite in diamond tilted 30 degrees: Light Return map, 22% of the face leaking30° · 22% 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: We have not measured a steeper DG-Octagonal Kite, so we offer none. DG-M5 Amethyst leaks 15%, the least we measure in quartz.

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

Far less light than the same kite in diamond

Brilliance 50 against 88 for the DG-Octagonal Kite in diamond: 38 points lower

Quartz's index near 1.55, against diamond's 2.417, changes what the pavilion does with light after the first reflection. In amethyst the kite returns 50, against 72 for the T73.

Dg-octagonal kite in amethyst face-up Light Return map: red, green and blue show where the light returns from, grey shows where it leaks (Brilliance 50)

DG-Octagonal Kite in amethyst · Brilliance 50

Dg-octagonal kite in diamond face-up Light Return map: red, green and blue show where the light returns from, grey shows where it leaks (Brilliance 88)

DG-Octagonal Kite in diamond · Brilliance 88

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 an eight-sided outline, the Octagon Cut Amethyst returns 64 in amethyst; the most light comes from DG-M5 Amethyst, 85.

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

Fewer flashes than the round

Scintillation 60 against 80 for the T73 Round Brilliant in amethyst: 20 points lower

41 large facets against the T73's 73: a bold pattern of kites rather than fine glitter. The diamond version scores the same.

DG-Octagonal Kite · 41 facets · Scintillation 60

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: For more sparkle in eight-fold symmetry, the Octagon Cut Amethyst scores 66; for a round, DG-Vitruvio Amethyst 98.

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

Who DG-Octagonal Kite in amethyst suits

DG-Octagonal Kite suits a bold, symmetrical amethyst centre stone, where its large table shows the colour and the kites give a clear pattern. In quartz it returns about two thirds of the round's light and holds it steadily when tipped.

For more light in eight sides, the Octagon Cut Amethyst. For how it behaves in emerald, see the DG-Octagonal Kite Emerald page.

DG-Octagonal Kite Amethyst: questions

Is DG-Octagonal Kite good for amethyst?

It trails the round on light, 50 against 72, and leaks 50%; it holds steady when tipped, Tilt 100.

DG-Octagonal Kite or octagon cut amethyst?

The octagon returns more light (64 against 50), leaks less (36% against 50%) and sparkles more; the kite holds steadier when tipped (100 against 83) and has a little more fire.

Why does DG-Octagonal Kite lose more light in amethyst than in diamond?

Same angles, different stone: quartz's critical angle is 40.4°, far wider than diamond's, so light the diamond holds can pass out of the pavilion. Our census measures 50% leakage here against 7% in diamond.

Get the DG-Octagonal Kite Cut files

6 formatsMillimetresWatertight

DG-Octagonal Kite Cut 3D files

The DG-Octagonal Kite Cut as exact geometry: 41 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

DG-Octagonal Kite Cut cutting files

The DG-Octagonal Kite Cut as a faceting design: 33 + 8 girdles = 41 facets, 96 index, 8-fold mirror-image 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.

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Amethyst: optical properties and the top ten cuts · The DG-Octagonal Kite: specifications, model and files

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The DG-Octagonal Kite in other gemstones