DG-Bowtie Diamond: Pros, Cons & Light Leakage

DG-Bowtie is the library's first marquise design, kept under its own name when the Marquise was remodelled. Our model has 87 facets on an outline 2.059 times as long as it is wide, a 42.0° pavilion and a depth of 93.8%.

Our Marquise Cut Diamond shares its facet count and ratio, cut far shallower. Side by side in diamond they differ sharply: the Marquise returns 64 for brilliance and faces up at 121, against 27 and 92 here.

We keep it to study beside the Marquise, and to render when a bow-tie is what you want to show.

Is DG-Bowtie a good cut for diamond? Pros and cons

Pros

A little more sparkle than a round 86 vs 80
A touch more fire than a round 82 vs 78

Cons

Less than a third of a round's light 27 vs 93
More than a third of the light leaks 36 vs 2
Keeps less light when tipped 83 vs 92
Smaller for its weight than a round 92 vs 100

Compared with the T73 Round Brilliant 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-Bowtie in diamond (white) against the T73 Round Brilliant in diamond (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 diamond: ahead on 2, behind on 6.

Global63, the comparison 90, difference −27
Brilliance27, the comparison 93, difference −66
Fire82, the comparison 78, difference +4
Scintillation86, the comparison 80, difference +6
Spread87, the comparison 100, difference −13
Symmetry94, the comparison 100, difference −6
Shape-norm31, the comparison 100, difference −69
Tilt83, the comparison 92, difference −9

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 DG-Bowtie gives a diamond

A little more sparkle than a round

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

Scintillation is read from the facets that reach the surface, and 87 is more than the T73's 73. The Marquise, with the same facet count, scores the same.

DG-Bowtie · 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

A touch more fire than a round

Fire 82 against 78 for the T73 Round Brilliant in diamond: 4 points higher

The margin is small, just past our threshold. Fire is a share of the light that returns, so it says nothing about how much comes back; the cons below do. Our Marquise shows more, 89.

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

T73 round brilliant in diamond face-up under a single bright light: a render from our simulator, its coloured flashes are the fire (score 78) — 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

Where DG-Bowtie falls short in diamond

Less than a third of a round's light

Brilliance 27 against 93 for the T73 Round Brilliant in diamond: 66 points lower

Only DG-Elongated Hexagon returns less in diamond. The pavilion, at 42.0°, is steeper than the 38.9° guide minimum.

Dg-bowtie in diamond face-up Light Return map: red, green and blue show where the light returns from, grey shows where it leaks (Brilliance 27) — 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 diamond face-up Light Return map: red, green and blue show where the light returns from, grey shows where it leaks (Brilliance 93) — 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: Our Marquise Cut Diamond keeps the outline and returns 64, the most of the elongated cuts we measure. Steepening is not the answer: this pavilion is already steeper than the Marquise's.

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

More than a third of the light leaks

Leakage 36 against 2 for the T73 Round Brilliant in diamond: 34 points higher

36% of the light in our census leaves through the back, against 2% for the T73 and 17% for our Marquise.

Dg-bowtie in diamond tilted 0 degrees: Light Return map, 47% 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.

Dg-bowtie in diamond tilted 10 degrees: Light Return map, 44% 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 share holds at any size. The Marquise Cut Diamond leaks 17%.

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

Keeps less light when tipped

Tilt 83 against 92 for the T73 Round Brilliant in diamond: 9 points lower

Tipped by 20° it keeps 83 of its face-up light, the T73 92. It starts with little light and loses a share of that too.

What helps: A round keeps more: the Old European Cut Diamond holds 93 when tipped.

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

Smaller for its weight than a round

Face-up size 92 against 100 for the T73 Round Brilliant in diamond (T73 = 100): 8% less face-up area for the same weight

On the same ratio, our Marquise faces up at 121. DG-Bowtie, at 93.8% deep, carries far more of its weight below the girdle and spreads less face per carat.

DG-Bowtie · 9.13 x 4.43 mm at 1.00 ct · Face-up size 92

T73 Round Brilliant · 6.48 mm at 1.00 ct · Face-up size 100

Both stones weigh 1.00 ct in diamond and are drawn to the same scale in millimetres, from each cut's own model. Face-up size is the outline's area per carat, with the T73 at 100: a deeper stone, or a rounder outline, spreads less area for its weight.

What helps: The Marquise Cut Diamond faces up at 121, level with the rectangle for the largest we measure in diamond.

Try it yourself: See its size at 1.00 ct in diamond in the 3D Gemstone Simulator

Who a DG-Bowtie diamond suits

Choose DG-Bowtie as a study piece or a render, beside the Marquise, or when a bow-tie is the effect you want to show. As a diamond to wear for its light, it is one of the weakest we measure.

For a marquise in diamond, choose our Marquise Cut Diamond: more light, more fire, less leakage and far more face for its weight, with the same sparkle.

DG-Bowtie Diamond: questions

What is the DG-Bowtie cut?

A marquise design kept under its own name when our Marquise was remodelled. It is 93.8% deep, nearly as deep as it is wide.

Does DG-Bowtie show a bow-tie?

Its name is for the dark band across the middle that elongated brilliants are prone to. We have no bow-tie metric, so we put no number on it; the census does show 36% of the light leaking.

DG-Bowtie or Marquise for a diamond?

Choose the Marquise. It returns 64 to DG-Bowtie's 27, leaks 17% to its 36%, and faces up at 121 to its 92; both score the same for scintillation.

What does a 6.5 mm wide DG-Bowtie diamond weigh?

3.16 ct, heavier than our Marquise at the same width. The likely reason is height: at 93.8% deep, it stands far taller on the same outline.

Get the DG-Bowtie Cut files

6 formatsMillimetresWatertight

DG-Bowtie Cut 3D files

The DG-Bowtie 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

DG-Bowtie Cut cutting files

The DG-Bowtie 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.

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DG-Bowtie Diamond: a touch more sparkle and fire than a round, at a heavy cost in light