Asscher Cut Sapphire: Pros, Cons & Tilt

The Asscher is a square step cut whose deeply cropped corners give it an octagonal outline over a stepped pavilion. Our model has 58 facets, is 60.4% deep and has a 27.6° pavilion figure.

In sapphire it returns almost exactly what the diamond Asscher does for light, 68 against 69. That makes its one pro a fair comparison: two stones with the same light, one keeping more of it at an angle.

The four cons shown are fire against diamond, light and leakage against the T73 Round Brilliant, and weight; scintillation, 72 against 80, also falls short.

Is an Asscher a good cut for sapphire? Pros and cons

Pros

Holds its light better than a diamond Asscher when tipped 85 vs 79

Cons

Less fire than the diamond Asscher 53 vs 80
Over a quarter less light than the T73 68 vs 94
Nearly three in ten rays leak 29 vs 5
Heavier than a diamond Asscher 1.53 vs 1.34 ct

Compared with the T73 Round Brilliant in sapphire and with the Asscher Cut 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 Asscher Cut in sapphire (white) against the T73 Round Brilliant in sapphire (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 sapphire: ahead on 3, level on 1, behind on 4.

Global72, the comparison 79, difference −7
Brilliance68, the comparison 94, difference −26
Fire53, the comparison 37, difference +16
Scintillation72, the comparison 80, difference −8
Spread107, the comparison 100, difference +7
Symmetry100, the comparison 100, difference 0
Shape-norm89, the comparison 102, difference −13
Tilt85, the comparison 75, difference +10

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 a sapphire gains as an Asscher

Holds its light better than a diamond Asscher when tipped

Tilt 85 against 79 for the Asscher Cut in diamond: 6 points higher

Tilted 20°, the sapphire keeps 85 of its face-up light, the diamond 79. Our tilt figure sets each stone against its own face-up light, and the two start level on brilliance, 68 and 69, so this lead is a real gain in steadiness.

Asscher cut in sapphire tilted 0 degrees: Light Return map, 31% of the face leaking — Tilt is how much of its own face-up light a stone keeps when tilted. 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.

Asscher cut in sapphire tilted 10 degrees: Light Return map, 30% of the face leaking — Tilt is how much of its own face-up light a stone keeps when tilted. 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.

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

Where the Asscher costs a sapphire

Less fire than the diamond Asscher

Fire 53 against 80 for the Asscher Cut in diamond: 27 points lower

Fire 53 against 80. The step pattern is the same in both stones, so the gap comes with the material, which our census changes as a whole. Against the T73 in sapphire, 37, it comes out ahead.

Asscher cut in sapphire face-up under a single bright light: a render from our simulator, its coloured flashes are the fire (score 53) — 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.

Asscher cut in diamond face-up under a single bright light: a render from our simulator, its coloured flashes are the fire (score 80) — 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

Over a quarter less light than the T73

Brilliance 68 against 94 for the T73 Round Brilliant in sapphire: 26 points lower

Brilliance 68 against 94. Level with the diamond Asscher's 69, it shows that in this cut sapphire gives up almost no light to diamond.

Asscher cut in sapphire face-up Light Return map: red, green and blue show where the light returns from, grey shows where it leaks (Brilliance 68) — 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 sapphire face-up Light Return map: red, green and blue show where the light returns from, grey shows where it leaks (Brilliance 94) — 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 with more light in sapphire, the Octagon Cut Sapphire returns 78 and the Square Cut Sapphire 78; DG-M5 Sapphire returns the most, 100.

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

Nearly three in ten rays leak

Leakage 29 against 5 for the T73 Round Brilliant in sapphire: 24 points higher

29% of the light in our census leaves through the pavilion, where the T73 loses 5% and the diamond Asscher 11%. Its 27.6° pavilion figure sits well under sapphire's 36.4° guide minimum.

What helps: We have not measured a steeper Asscher, so we cannot promise what one would keep. The Square Cut Sapphire leaks 16%, the Octagon Cut Sapphire 20%.

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

Heavier than a diamond Asscher

1.53 ct at 6.5 mm, against 1.34 ct for the same cut in diamond (+14%)

Edge to edge at 6.5 mm, it weighs 1.53 ct in sapphire against 1.34 ct in diamond. Sapphire is the denser stone, 4.00 against 3.52.

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

What helps: Specify it by edge length.

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

Who an Asscher sapphire suits

The Asscher suits a clean sapphire with even colour in an Art Deco or geometric design, and a ring that will often be seen at an angle, where its steady light is the measured strength.

If you want more light in a square, the Octagon Cut Sapphire or the Square Cut Sapphire. Rounds return the most, and DG-M5 Sapphire tops our sapphire census.

Asscher Cut Sapphire: questions

Is an Asscher cut good for sapphire?

For steady light, yes: it keeps 85 of its light tipped 20°, more than the diamond Asscher's 79. Face-up it is less bright than a round: Brilliance 68 to the T73's 94.

Asscher or emerald square cut for a sapphire?

The emerald square returns a little more light (71 against 68) and leaks less (22% against 29%); the two hold their light about equally when tipped, 86 and 85.

Does an Asscher sapphire have fire?

Fire 53: more than the T73 in sapphire (37), far less than the diamond Asscher (80).

What does a 6.5 mm Asscher sapphire weigh?

About 1.53 ct in sapphire and 1.34 ct in diamond, from the model's measured volume.

Get the Asscher Cut files

6 formatsMillimetresWatertight

Asscher Cut 3D files

The Asscher Cut as exact geometry: 58 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

Asscher Cut cutting files

The Asscher Cut as a faceting design: 58 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

Sapphire: optical properties and the top ten cuts · The Asscher Cut: specifications, model and files

Asscher Cut Sapphire: holds its light at a tilt better than the diamond version