Marquise Cut Amethyst: Pros, Cons & Leakage

A marquise is a long brilliant that comes to a point at each end; some call it a navette. Ours is 2.059 times as long as it is wide, with 87 facets, a 31.41° pavilion and 62.0% depth.

That pavilion is far under the 40.4° guide minimum, which is worked out for rounds; we have not measured a steeper marquise and do not promise one. What we measure is the cut as drawn: 59% leakage in amethyst against 17% in diamond.

Its spread is level with the T73's, 100 against 100: for its weight, our census finds it no larger face-up than the round.

Is a marquise a good cut for amethyst? Pros and cons

Pros

Lighter than diamond 1.57 vs 2.09 ct
A little more sparkle than the T73 86 vs 80

Cons

Well over half the light leaks 59 vs 17
About half the diamond marquise's fire 48 vs 89
About half the T73's light 38 vs 72
Loses more light when tipped 71 vs 87

Compared with the T73 Round Brilliant in amethyst and with the Marquise 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 Marquise 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.

Against the T73 Round Brilliant in amethyst: ahead on 2, level on 1, behind on 5.

Global56, the comparison 70, difference −14
Brilliance38, the comparison 72, difference −34
Fire48, the comparison 36, difference +12
Scintillation86, the comparison 80, difference +6
Spread100, the comparison 100, difference 0
Symmetry94, the comparison 100, difference −6
Shape-norm44, the comparison 77, difference −33
Tilt71, the comparison 80, difference −9

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 a marquise

Lighter than diamond

1.57 ct at 6.5 mm, against 2.09 ct for the same cut in diamond (−25%)

Because it is long, a marquise 6.5 mm wide is a big stone: 1.57 ct in amethyst, 2.09 ct in diamond.

A Marquise 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 Marquise Cut page

A little more sparkle than the T73

Scintillation 86 against 80 for the T73 Round Brilliant in amethyst: 6 points higher

87 facets along a long outline give our facet-based scintillation score more than the round's 73.

Marquise Cut · 87 facets · Scintillation 86

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

The catch with a marquise amethyst

Well over half the light leaks

Leakage 59 against 17 for the Marquise Cut in diamond: 42 points higher

In the diamond marquise 17% leaks; in amethyst it is 59%, more than the oval, pear or teardrop lose in this stone.

Marquise cut in amethyst tilted 0 degrees: Light Return map, 54% 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.

Marquise cut in amethyst tilted 10 degrees: Light Return map, 64% 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: The Pear Cut Amethyst leaks 39% in amethyst, the Oval Cut Amethyst 43%. Size does not change the share.

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

About half the diamond marquise's fire

Fire 48 against 89 for the Marquise Cut in diamond: 41 points lower

Weak dispersion in quartz, and less light returning to carry colour: 48 where the diamond version reaches 89.

Marquise cut in amethyst face-up under a single bright light: a render from our simulator, its coloured flashes are the fire (score 48) — 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.

Marquise cut in diamond face-up under a single bright light: a render from our simulator, its coloured flashes are the fire (score 89) — 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: A wider, shorter outline brings more colour: the Oval Cut Amethyst scores 69 here.

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

About half the T73's light

Brilliance 38 against 72 for the T73 Round Brilliant in amethyst: 34 points lower

The long points and the middle return little, and marquises are prone to a dark bow-tie across the centre, which we do not measure.

Marquise cut in amethyst face-up Light Return map: red, green and blue show where the light returns from, grey shows where it leaks (Brilliance 38) — 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 amethyst face-up Light Return map: red, green and blue show where the light returns from, grey shows where it leaks (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: The Oval Cut Amethyst and the Pear Cut Amethyst return 52 and 52.

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

Loses more light when tipped

Tilt 71 against 87 for the Marquise Cut in diamond: 16 points lower

Tipped by 20°, it keeps 71 of its face-up light, against 87 for the diamond marquise.

What helps: A shorter outline helps: the Oval Cut Amethyst holds 74 at 20°.

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

Who a marquise amethyst suits

Choose the marquise in amethyst for its long outline in a ring or a cluster, where shape leads. The points need protection, usually with V-prongs, and quartz at hardness 7 makes that more important.

For an elongated amethyst, the Oval Cut Amethyst does better here on light, fire, leakage and tilt, and sparkles as much.

Weigh it by millimetres rather than carats: a long stone carries more than its width suggests.

Marquise Cut Amethyst: questions

Is a marquise cut good for amethyst?

Not for light: Brilliance 38 against 72 for the T73, with 59% leakage.

Does a marquise amethyst look bigger?

Not for its weight, in our census: Spread 100 against 100 for the round. It is long, so it looks larger along one axis.

Marquise or oval amethyst?

In amethyst the oval wins on all three counts that matter most here: Brilliance 52 to 38, Fire 69 to 48, leakage 43% to 59%.

What does a marquise amethyst 6.5 mm wide weigh?

1.57 ct, against 2.09 ct in diamond.

Get the Marquise Cut files

6 formatsMillimetresWatertight

Marquise Cut 3D files

The Marquise Cut as exact geometry: 87 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

GemCad64 index

Marquise Cut cutting files

The Marquise Cut as a faceting design: 67 + 20 girdles = 87 facets, 64 index, 2-fold mirror-image symmetry, ready for the machine.

.ascGemCad design file, 64 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 Marquise Cut: specifications, model and files

Marquise Cut Amethyst: more sparkle than a round, and lighter in weight than diamond