Cushion Cut Ruby: Pros, Cons & Brilliance

Ours is the modern brilliant cushion: a square with rounded corners, 85 facets, a 39.56° pavilion and a deep 65.0% profile.

In ruby it returns 88 for brilliance. That is more than the cushion in diamond (80) and less than the T73 in ruby (94); our rule counts the larger gap, so brilliance appears here as a pro. Sparkle edges past the T73 too.

The cushion follows the chunky, rounded rough some rubies come as, which is one reason it is so common in this stone.

Does a cushion cut suit ruby? Pros and cons

Pros

More light than a diamond cushion 88 vs 80
A little more sparkle than the T73 85 vs 80

Cons

Much less fire than a diamond cushion 36 vs 73
Holds less light when tilted 72 vs 92
Deep and dense 1.44 vs 1.27 ct
A little more leakage than a round 11 vs 5

Compared with the T73 Round Brilliant in ruby and with the Cushion 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 Cushion Cut in ruby (white) against the T73 Round Brilliant in ruby (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 ruby: ahead on 2, behind on 6.

Global76, the comparison 79, difference −3
Brilliance88, the comparison 94, difference −6
Fire36, the comparison 37, difference −1
Scintillation85, the comparison 80, difference +5
Spread98, the comparison 100, difference −2
Symmetry97, the comparison 100, difference −3
Shape-norm103, the comparison 102, difference +1
Tilt72, the comparison 75, difference −3

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 ruby gains in a cushion

More light than a diamond cushion

Brilliance 88 against 80 for the Cushion Cut in diamond: 8 points higher

The ruby cushion scores 88 for brilliance, the diamond cushion 80. The cushion's angles seem to suit corundum's lower refractive index better than diamond's; the T73 in ruby still returns more, 94.

Cushion cut in ruby face-up Light Return map: red, green and blue show where the light returns from, grey shows where it leaks (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.

Cushion cut in diamond face-up Light Return map: red, green and blue show where the light returns from, grey shows where it leaks (Brilliance 80) — 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.

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

A little more sparkle than the T73

Scintillation 85 against 80 for the T73 Round Brilliant in ruby: 5 points higher

With 85 facets against 73, the scintillation score sits a few points above the T73's.

Cushion Cut · 85 facets · Scintillation 85

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

Where the cushion costs a ruby

Much less fire than a diamond cushion

Fire 36 against 73 for the Cushion Cut in diamond: 37 points lower

Fire 36 against 73: corundum's 0.018 dispersion against diamond's 0.044, through the same facets.

Cushion cut in ruby face-up under a single bright light: a render from our simulator, its coloured flashes are the fire (score 36) — 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.

Cushion cut in diamond face-up under a single bright light: a render from our simulator, its coloured flashes are the fire (score 73) — 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: Fire is where corundum is weakest in every shape; stretching to an Oval Cut Ruby lifts it to 74.

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

Holds less light when tilted

Tilt 72 against 92 for the Cushion Cut in diamond: 20 points lower

Tipped 20°, the ruby cushion keeps 72 of its face-up light, the diamond cushion 92. It is the lowest tilt score of our square-outline ruby pages.

Cushion cut in ruby tilted 0 degrees: Light Return map, 7% 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.

Cushion cut in ruby tilted 10 degrees: Light Return map, 16% 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.

What helps: The Square Cut Ruby keeps 84 at 20° in ruby, with less light (78).

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

Deep and dense

1.44 ct at 6.5 mm, against 1.27 ct for the same cut in diamond (+14%)

A 65.0% deep cushion in a stone denser than diamond: 1.44 ct at 6.5 mm in ruby, 1.27 ct in diamond.

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

What helps: Cushion settings follow the outline, so order by millimetres.

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

A little more leakage than a round

Leakage 11 against 5 for the T73 Round Brilliant in ruby: 6 points higher

The ruby cushion loses 11% through the back, the T73 5%. It is low for a fancy shape: only the trilliant comes close among our non-round ruby pages.

What helps: The 39.56° pavilion already clears ruby's 36.4° guide minimum, so a steeper one is not the fix our data supports. A round leaks less: DG-Anteros Ruby 3%.

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

Who a cushion ruby suits

If a ruby is not to be round, the cushion is the shape our numbers favour: the most light and the least leakage of the non-round cuts on our ruby pages. A vintage-style ruby ring is the natural home for it.

Only rounds return more light in ruby, led by DG-M5 Ruby; for colour flashes, the Oval Cut Ruby.

Cushion Cut Ruby: questions

Is a cushion a good cut for ruby?

Yes, in our census: Brilliance 88 and 11% leakage, the best of the non-round shapes we measure in ruby.

Cushion ruby or oval ruby?

The cushion returns more light (88 against 66) and leaks less; the oval has far more fire (74 against 36).

What does a 6.5 mm cushion ruby weigh?

Its deep profile makes a 6.5 mm ruby cushion about 1.44 ct; in diamond, 1.27 ct.

Does the cushion show a ruby's colour well?

We do not measure colour. Light return carries the body colour to the eye, and this cushion returns more than any other non-round ruby we measure.

Get the Cushion Cut files

6 formatsMillimetresWatertight

Cushion Cut 3D files

The Cushion Cut as exact geometry: 85 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

Cushion Cut cutting files

The Cushion Cut as a faceting design: 69 + 16 girdles = 85 facets, 96 index, 2-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.

More gemstones and cuts

Ruby: optical properties and the top ten cuts · The Cushion Cut: specifications, model and files

Cushion Cut Ruby: more light than a diamond cushion, and fine sparkle