Brilliance 85 · Fire 63 · Scintillation 79 · in our census, where the T73 scores 94 · 50 · 80 in pyrope
How the Trilliant Cut handles light in pyrope, measured: brilliance 85, fire 63 and 13% leakage, set against the T73 in the same stone and against the same cut in diamond.
Pyrope has a refractive index of 1.730 to 1.766 and a dispersion of 0.022. Its critical angle, from the low end of that range, is 35.3°, so a round design needs a pavilion of at least 36.2° for head-on light to reflect off both sides of the pavilion and leave through the table. We trace it with one index, 1.748, the midpoint of the published range, and a fire spread of 0.019, 0.86 of the published dispersion. Every picture here is our Light Return tracer at 1.730, and every figure is from the same light census that scores the other gemstones; the 3D Gemstone Simulator shows the Trilliant Cut in pyrope live.
The Trilliant Cut has 70 facets and a total depth of 58.9% of its width; its pavilion mains sit at 39.0°. In pyrope, the census returns 85 of 100 for brilliance and 63 for fire, against 94 and 50 for the T73, our benchmark, in the same stone; the same Trilliant Cut in diamond reads 78 and 83.
No figure ahead by our thresholds
Compared with the T73 Round Brilliant in pyrope and with the Trilliant 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.
At a glance: the Trilliant Cut in pyrope (white) against the T73 Round Brilliant in pyrope (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 pyrope: ahead on 2, behind on 6.
Against the T73 in pyrope and the same cut in diamond, no figure of the Trilliant Cut is ahead by the thresholds above. Its figures are in the wheel and the FAQ; Pyrope ranks every cut we score in pyrope.
Symmetry 62 against 100 for the T73 Round Brilliant in pyrope: 38 points lower
Symmetry reads how evenly the pavilion facets of each design family are cut: 100 − 6 × their scatter in degrees. The Trilliant Cut reads 62, the T73 100. It depends on the geometry alone, so it is the same in every stone.
Trilliant Cut · 70 facets · Symmetry 62
T73 Round Brilliant · 73 facets · Symmetry 100
Try it yourself: Compare the Symmetry spoke in the Cut Performance Wheel
Fire 63 against 83 for the Trilliant Cut in diamond: 20 points lower
Fire is the share of the returned light that splits into color at the exit facet: the census traces each exit again at the refractive index minus and plus the fire spread (0.019 in pyrope) and counts a ray as fire when the two directions differ by more than 0.6°. The Trilliant Cut reads 63 against 83 for the same cut in diamond. The figure is the census's; the 3D Gemstone Simulator renders pyrope's fire live.
The fire figure is the census's, traced at the refractive index minus and plus the fire spread. See the fire in the 3D Gemstone Simulator: the Trilliant Cut in pyrope under the sunny-day lighting.
What helps: the DG-Elongated Hexagon reads 85 for fire in pyrope, the best of the cuts we score there.
Tilt 74 against 89 for the Trilliant Cut in diamond: 15 points lower
Tilt is how much of its face-up brilliance a stone keeps when the census tilts it 20° about its long axis, with 2,200 rays. The Trilliant Cut keeps 74 against 89 for the same cut in diamond. The tilt strips below show the maps at 0°, 10°, 20° and 30°, with each picture's own leak share under it.
Trilliant Cut in pyrope · Tilt 74
Trilliant Cut in diamond · Tilt 89
What helps: the DG-Miliano reads 83 for tilt in pyrope, the best of the cuts we score there.
Try it yourself: Compare the Tilt spoke in the Cut Performance Wheel
Brilliance 85 against 94 for the T73 Round Brilliant in pyrope: 9 points lower
Brilliance is the share of the 3,200 census rays that enter the stone and come back out of the crown towards the viewer. In pyrope, whose critical angle is 35.3°, the Trilliant Cut returns 85 of 100 and the T73 94. The Trilliant Cut's pavilion mains sit at 39.0°, the T73's at 40.8°. The maps below show where each stone's light returns from and where it leaks.
Trilliant Cut in pyrope · Brilliance 85
T73 Round Brilliant in pyrope · Brilliance 94
What helps: the DG-M5 reads 100 for brilliance in pyrope, the best of the cuts we score there.
Try it yourself: Open this Light Return map in the simulator
Against the T73 in pyrope and the same cut in diamond, no figure of the Trilliant Cut is ahead by our thresholds. The catch: it has a less regular pavilion than the T73, shows less fire than in diamond, loses more light when tilted than in diamond and returns less light than the T73.
If that catch matters more to you, the DG-Elongated Hexagon reads 85 for fire in pyrope, the best of the cuts we score there.
Every figure on this page is from our light census, traced at one refractive index: a simulation of the geometry, not a grading report. The 3D files and cutting files below are the same Trilliant Cut model we traced.
In our census the Trilliant Cut returns 85 of 100 for brilliance and 63 for fire in pyrope, against 94 and 50 for the T73 in the same stone. Against that round and against the same cut in diamond it has 0 pros and 4 cons by our thresholds; the summary above names them.
At least 36.2° for a round design: pyrope's critical angle is 35.3°, from the low end of its refractive index range, and head-on light has to reflect off both sides of the pavilion and leave through the table. The Trilliant Cut's pavilion mains sit at 39.0°.
At 6.5 mm across, 1.02 ct in pyrope, against 0.96 ct for the same cut in diamond (+7%): pyrope's specific gravity is 3.76, diamond's 3.52.
Yes: the 3D Gemstone Simulator renders it live, with pyrope's own refractive index and dispersion. Pyrope is traced by the same light census as the other gemstones, with its refractive index and fire spread derived from published values, so its scores are on the same scale; the pictures here are our Light Return tracer, and the Cut Performance Wheel sets it against any other cut and stone.
The Trilliant Cut as exact geometry: 72 planar facets, real-world scale, ready for CAD, rendering, printing and casting.
The Trilliant Cut as a faceting design: 58 + 12 girdles = 70 facets, 96 index, 3-fold mirror-image symmetry, ready for the machine.
Not sure the files open in your software? Get the cube free: the same six formats, for your email address, used only to send them (privacy).
Questions before you buy? Email us.
Pyrope: optical properties and the top ten cuts · The Trilliant Cut: specifications, model and files