---
title: "Emerald Cut Iolite: Pros, Cons and Scores"
description: "Emerald Cut in iolite: brilliance 53, fire 53, leakage 41%, 2 pros and 4 cons against the T73, from our ray-traced light census."
url: https://digitalgemology.com/gemstones/iolite/emerald-cut
image: https://digitalgemology.com/img/stone-cuts/emerald-cut-iolite-og.jpg?v=d3f0f506
---

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# Emerald Cut Iolite: lighter than the same cut in diamond

**Buy (instant download, personal-use license):** [Emerald Cut 3D files, €9.99 · Personal use](https://digitalgemology.lemonsqueezy.com/checkout/buy/7a254e34-3548-40df-9016-7f9f42e19852) · [Emerald Cut cutting files, €6.99 · Personal use](https://digitalgemology.lemonsqueezy.com/checkout/buy/6fc2df4f-3220-428e-94ba-367bdcc8ecb6) · [Buy the bundle](https://digitalgemology.lemonsqueezy.com/checkout/buy/e5c79ed5-97ce-4c62-8dbe-3a172c6245ba?checkout%5Bdiscount_code%5D=BUNDLE25) · [Buy the bundle](https://digitalgemology.lemonsqueezy.com/checkout/buy/9170b0c0-5357-490e-b6ef-3ce4f7fcd282?checkout%5Bdiscount_code%5D=BUNDLE25) · [Get the cube free](https://digitalgemology.lemonsqueezy.com/checkout/buy/2d1ab55f-2bd6-4897-a4cd-f3320f54e99e)

Brilliance 53 · Fire 53 · Scintillation 72 · in our census, where the T73 scores 72 · 58 · 80 in iolite

How the Emerald Cut handles light in iolite, measured: brilliance 53, fire 53 and 41% leakage, set against the T73 in the same stone and against the same cut in diamond.

[Get the files](https://digitalgemology.com/gemstones/iolite/emerald-cut#buy) [Open it in the Simulator](https://digitalgemology.com/tools/3d_gemstone_simulator?cut=emerald-cut&stone=iolite&ct=1.00&view=angle&lighting=studio&turn=0) [All cuts in iolite](https://digitalgemology.com/gemstones/iolite)

Light Return map of the Emerald Cut in iolite, face-up, from our own tracer at refractive index 1.542. Red, green and blue return light to the eye; gray leaks.

## Emerald Cut Iolite

Iolite has a refractive index of 1.542 to 1.551 and a dispersion of 0.017. Its critical angle, from the low end of that range, is 40.4°, so a round design needs a pavilion of at least 40.4° for head-on light to reflect off both sides of the pavilion and leave through the table. We trace it with one index, 1.547, the midpoint of the published range, and a fire spread of 0.015, 0.86 of the published dispersion. Every picture here is our Light Return tracer at 1.542, and every figure is from the same light census that scores the other gemstones; the 3D Gemstone Simulator shows the Emerald Cut in iolite live.

The Emerald Cut has 57 facets and a total depth of 68.6% of its width; its pavilion mains sit at 41.0°. In iolite, the census returns 53 of 100 for brilliance and 53 for fire, against 72 and 58 for the T73, our benchmark, in the same stone; the same Emerald Cut in diamond reads 55 and 87.

## Is iolite good in an Emerald? Pros and cons, measured

### Pros

- [Lighter than the same cut in diamond](https://digitalgemology.com/gemstones/iolite/emerald-cut#pro-weight) 1.72 vs 2.31 ct
- [Faces up larger for its weight](https://digitalgemology.com/gemstones/iolite/emerald-cut#pro-faceup) 105 vs 100

### Cons

- [A less regular pavilion than the T73](https://digitalgemology.com/gemstones/iolite/emerald-cut#con-symm) 64 vs 100
- [Less fire in iolite than in diamond](https://digitalgemology.com/gemstones/iolite/emerald-cut#con-fire) 53 vs 87
- [Loses more light when tilted than in diamond](https://digitalgemology.com/gemstones/iolite/emerald-cut#con-tiltStab) 54 vs 83
- [Returns less light than the T73 in iolite](https://digitalgemology.com/gemstones/iolite/emerald-cut#con-brilliance) 53 vs 72

Compared with the T73 Round Brilliant in iolite and with the Emerald 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](https://digitalgemology.com/about/how-we-measure).

## All eight scores against the T73

At a glance: the Emerald Cut in iolite (white) against the T73 Round Brilliant in iolite (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 iolite: behind on 8.

- Global 57, the comparison 74, difference −17
- Brilliance 53, the comparison 72, difference −19
- Fire 53, the comparison 58, difference −5
- Scintillation 72, the comparison 80, difference −8
- Spread 96, the comparison 100, difference −4
- Symmetry 64, the comparison 100, difference −36
- Shape-norm 69, the comparison 77, difference −8
- Tilt 54, the comparison 81, difference −27

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](https://digitalgemology.com/tools/cut-performance-wheel?cut=emerald-cut&stone=iolite); these are the same census figures as our [Cut Performance Index](https://digitalgemology.com/learn/cut-performance-index).

## What the Emerald Cut gains in iolite

### Lighter than the same cut in diamond

**1.72 ct** at 6.5 mm, against 2.31 ct for the same cut in diamond (−26%)

Weight follows specific gravity: 2.61 for iolite against 3.52 for diamond, so the same model at the same size weighs 1.72 ct here and 2.31 ct in diamond, 6.5 mm across. Nothing about the light changes with it.

*Weight of a 6.5 mm Emerald Cut: 1.72 ct in iolite, 2.31 ct in diamond*

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

[Try it yourself: Weights in every gemstone on the Emerald Cut page](https://digitalgemology.com/cuts/emerald-cut#stones)

### Faces up larger for its weight

**Face-up size 105** against 100 for the T73 Round Brilliant in iolite (T73 = 100): 5% more face-up area for the same weight

Face-up size is the outline's area per carat, measured from each model (T73 = 100): 105 for the Emerald Cut against 100 for the T73. The same volume spread over a longer or shallower outline shows more face for the weight; it is the same in every stone, because specific gravity scales every cut alike.

*Face-up outline of the Emerald Cut at 1.00 ct in iolite: 8.13 x 5.42 mm, drawn to scale*

Emerald Cut · 8.13 x 5.42 mm at 1.00 ct · Face-up size 105

*Face-up outline of the T73 Round Brilliant at 1.00 ct in iolite: 7.15 mm, drawn to scale*

T73 Round Brilliant · 7.15 mm at 1.00 ct · Face-up size 100

Both stones weigh 1.00 ct in iolite and are drawn to the same scale in millimeters, 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.

[Try it yourself: See its size at 1.00 ct in iolite in the 3D Gemstone Simulator](https://digitalgemology.com/tools/3d_gemstone_simulator?cut=emerald-cut&stone=iolite&ct=1.00&view=up&lighting=studio&turn=0)

## What the Emerald Cut gives up in iolite

### A less regular pavilion than the T73

**Symmetry 64** against 100 for the T73 Round Brilliant in iolite: 36 points lower

Symmetry reads how evenly the pavilion facets of each design family are cut: 100 − 6 × their scatter in degrees. The Emerald Cut reads 64, the T73 100. It depends on the geometry alone, so it is the same in every stone.

*Facet diagram of the Emerald Cut: its pavilion, seen from below, 57 facets in all*

Emerald Cut · 57 facets · Symmetry 64

*Facet diagram of the T73 Round Brilliant: its pavilion, seen from below, 73 facets in all*

T73 Round Brilliant · 73 facets · Symmetry 100

Symmetry scores how regular the pavilion facets are within the design. Compare how evenly the facets repeat around each pavilion. Drawn from each cut's own model.

[Try it yourself: Compare the Symmetry spoke in the Cut Performance Wheel](https://digitalgemology.com/tools/cut-performance-wheel?cut=emerald-cut&stone=iolite)

### Less fire in iolite than in diamond

**Fire 53** against 87 for the Emerald Cut in diamond: 34 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 (0.015 in iolite) and counts a ray as fire when the two directions differ by more than 0.6°. The Emerald Cut reads 53 against 87 for the same cut in diamond. The figure is the census's; the 3D Gemstone Simulator renders iolite'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](https://digitalgemology.com/tools/3d_gemstone_simulator?cut=emerald-cut&stone=iolite&ct=1.00&view=up&lighting=sun&turn=0): the Emerald Cut in iolite under the sunny-day lighting.

**What helps:** [the Oval Cut](https://digitalgemology.com/gemstones/iolite/oval) reads 82 for fire in iolite, the best of the cuts we score there.

[Try it yourself: See the fire in the 3D Gemstone Simulator](https://digitalgemology.com/tools/3d_gemstone_simulator?cut=emerald-cut&stone=iolite&ct=1.00&view=up&lighting=sun&turn=0)

### Loses more light when tilted than in diamond

**Tilt 54** against 83 for the Emerald Cut in diamond: 29 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 Emerald Cut keeps 54 against 83 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.

Emerald Cut in iolite · Tilt 54

0° · 28% leak

10° · 52% leak

20° · 58% leak

30° · 68% leak

Emerald Cut in diamond · Tilt 83

0° · 31% leak

10° · 31% leak

20° · 38% leak

30° · 44% leak

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; gray is leakage. The share under each frame is that picture's own.

**What helps:** [the T105 Round Brilliant](https://digitalgemology.com/gemstones/iolite/t105-round-brilliant) reads 87 for tilt in iolite, the best of the cuts we score there.

[Try it yourself: Compare the Tilt spoke in the Cut Performance Wheel](https://digitalgemology.com/tools/cut-performance-wheel?cut=emerald-cut&stone=iolite&vs=emerald-cut&vsstone=diamond)

### Returns less light than the T73 in iolite

**Brilliance 53** against 72 for the T73 Round Brilliant in iolite: 19 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 iolite, whose critical angle is 40.4°, the Emerald Cut returns 53 of 100 and the T73 72. The Emerald Cut's pavilion mains sit at 41.0°, the T73's at 40.8°. The maps below show where each stone's light returns from and where it leaks.

Emerald Cut in iolite · Brilliance 53

T73 Round Brilliant in iolite · Brilliance 72

Red, green and blue = light returning to the eye; gray = leakage, light that leaves heading down or stays inside. 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 DG-M5](https://digitalgemology.com/gemstones/iolite/dg-m5) reads 85 for brilliance in iolite, the best of the cuts we score there.

[Try it yourself: Open this Light Return map in the simulator](https://digitalgemology.com/tools/3d_gemstone_simulator?cut=emerald-cut&stone=iolite&ct=1.00&view=up&map=1&turn=0)

## Our verdict on the Emerald Cut in iolite

Pick the Emerald Cut in iolite for this: it weighs less than in diamond and faces up larger for its weight. 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 Oval Cut](https://digitalgemology.com/gemstones/iolite/oval) reads 82 for fire in iolite, 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 Emerald Cut model we traced.

## Emerald Cut Iolite: questions

### Is the Emerald a good cut for iolite?

In our census the Emerald Cut returns 53 of 100 for brilliance and 53 for fire in iolite, against 72 and 58 for the T73 in the same stone. Against that round and against the same cut in diamond it has 2 pros and 4 cons by our thresholds; the summary above names them.

### What pavilion angle does iolite need?

At least 40.4° for a round design: iolite's critical angle is 40.4°, 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 Emerald Cut's pavilion mains sit at 41.0°.

### How much does a Emerald weigh in iolite?

At 6.5 mm across, 1.72 ct in iolite, against 2.31 ct for the same cut in diamond (-26%): iolite's specific gravity is 2.61, diamond's 3.52.

### Can I see the Emerald in iolite in 3D?

Yes: the 3D Gemstone Simulator renders it live, with iolite's own refractive index and dispersion. Iolite 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.

## Get the Emerald Cut files

*6 formats* *Millimeters* *Watertight*

### Emerald Cut 3D files

The Emerald Cut as exact geometry: 57 planar facets, real-world scale, ready for CAD, rendering, printing and casting.

- **STEP** Exact faceted solid for CAD
- **3DM** Rhino, closed mesh on its own layer
- **STL** Watertight mesh for printing and casting
- **OBJ** Mesh for modeling and rendering
- **FBX** Blender, 3ds Max, Maya, Cinema 4D, Unity, Unreal
- **GLB** Web, AR and quick previews

€9.99 · [Personal use](https://digitalgemology.com/licence) [Buy the 3D files](https://digitalgemology.lemonsqueezy.com/checkout/buy/7a254e34-3548-40df-9016-7f9f42e19852)

*GemCad* *64 index*

### Emerald Cut cutting files

The Emerald Cut as a faceting design: 49 + 8 girdles = 57 facets, 64 index, 2-fold mirror-image symmetry, ready for the machine.

- **.asc** GemCad design file, 64 index gear
- **.csv** Tier table: angles, indices and cutting order
- **Diagram** Printable faceting diagram

€6.99 · [Personal use](https://digitalgemology.com/licence) [Buy the cutting files](https://digitalgemology.lemonsqueezy.com/checkout/buy/6fc2df4f-3220-428e-94ba-367bdcc8ecb6)

Save with a bundle: the Emerald Cut 3D files are also in [Jewelry Essentials 3D](https://digitalgemology.com/cuts/#bundles), 10 cuts for €29.99 until 1 December, then €39.99 (€99.90 as single files). [Buy the bundle](https://digitalgemology.lemonsqueezy.com/checkout/buy/e5c79ed5-97ce-4c62-8dbe-3a172c6245ba?checkout%5Bdiscount_code%5D=BUNDLE25).

Save with a bundle: the Emerald Cut cutting files are also in [Faceter's Classics](https://digitalgemology.com/cuts/#bundles), 10 cuts for €22.49 until 1 December, then €29.99 (€69.90 as single files). [Buy the bundle](https://digitalgemology.lemonsqueezy.com/checkout/buy/9170b0c0-5357-490e-b6ef-3ce4f7fcd282?checkout%5Bdiscount_code%5D=BUNDLE25).

Not sure the files open in your software? [Get the cube free](https://digitalgemology.lemonsqueezy.com/checkout/buy/2d1ab55f-2bd6-4897-a4cd-f3320f54e99e): the same six formats, for your email address, used only to send them ([privacy](https://digitalgemology.com/privacy#free-sample)).

Questions before you buy? [Email us](mailto:support@digitalgemology.com).

## More gemstones and cuts

[Iolite: optical properties and the top ten cuts](https://digitalgemology.com/gemstones/iolite) · [The Emerald Cut: specifications, model and files](https://digitalgemology.com/cuts/emerald-cut)

### Other cuts in iolite

- [T73 Round Brilliant](https://digitalgemology.com/gemstones/iolite/t73-round-brilliant)
- [T105 Round Brilliant](https://digitalgemology.com/gemstones/iolite/t105-round-brilliant)
- [DG-Vitruvio](https://digitalgemology.com/gemstones/iolite/dg-vitruvio)
- [DG-Anteros](https://digitalgemology.com/gemstones/iolite/dg-anteros)
- [DG-Broken Hearts and Arrows](https://digitalgemology.com/gemstones/iolite/dg-broken-hearts-and-arrows)
- [Baguette Cut](https://digitalgemology.com/gemstones/iolite/baguette)
- [Marquise Cut](https://digitalgemology.com/gemstones/iolite/marquise)
- [Oval Cut](https://digitalgemology.com/gemstones/iolite/oval)
- [Pear Cut](https://digitalgemology.com/gemstones/iolite/pear)
- [Radiant Cut](https://digitalgemology.com/gemstones/iolite/radiant)
- [Rectangle Cut](https://digitalgemology.com/gemstones/iolite/rectangle)
- [Teardrop Cut](https://digitalgemology.com/gemstones/iolite/teardrop)
- [Asscher Cut](https://digitalgemology.com/gemstones/iolite/asscher)
- [Cushion Cut](https://digitalgemology.com/gemstones/iolite/cushion)
- [Emerald Square Cut](https://digitalgemology.com/gemstones/iolite/emerald-square)
- [Princess Cut](https://digitalgemology.com/gemstones/iolite/princess)
- [Radiant Square Cut](https://digitalgemology.com/gemstones/iolite/radiant-square)
- [Square Cut](https://digitalgemology.com/gemstones/iolite/square)
- [Triangle Cut](https://digitalgemology.com/gemstones/iolite/triangle)
- [Trilliant Cut](https://digitalgemology.com/gemstones/iolite/trilliant)
- [Trillion Cut](https://digitalgemology.com/gemstones/iolite/trillion)
- [Hexagon Cut](https://digitalgemology.com/gemstones/iolite/hexagon)
- [Octagon Cut](https://digitalgemology.com/gemstones/iolite/octagon)
- [Portuguese Bird's Nest Cut](https://digitalgemology.com/gemstones/iolite/portuguese-birds-nest)
- [Old Single Cut](https://digitalgemology.com/gemstones/iolite/old-single)
- [Mazarin Cut](https://digitalgemology.com/gemstones/iolite/mazarin)
- [Peruzzi Cut](https://digitalgemology.com/gemstones/iolite/peruzzi)
- [Old Mine Cut](https://digitalgemology.com/gemstones/iolite/old-mine)
- [Old European Cut](https://digitalgemology.com/gemstones/iolite/old-european)
- [T57 Round Brilliant](https://digitalgemology.com/gemstones/iolite/t57-round-brilliant)
- [DG-M5](https://digitalgemology.com/gemstones/iolite/dg-m5)
- [DG-Miliano](https://digitalgemology.com/gemstones/iolite/dg-miliano)
- [DG-Rafaello](https://digitalgemology.com/gemstones/iolite/dg-rafaello)
- [DG-Bowtie](https://digitalgemology.com/gemstones/iolite/dg-bowtie)
- [DG-Elongated Hexagon](https://digitalgemology.com/gemstones/iolite/dg-elongated-hexagon)
- [DG-Octagonal Kite](https://digitalgemology.com/gemstones/iolite/dg-octagonal-kite)

### The Emerald Cut in other gemstones

- [Diamond](https://digitalgemology.com/gemstones/diamond/emerald-cut)
- [Moissanite](https://digitalgemology.com/gemstones/moissanite/emerald-cut)
- [Cubic Zirconia](https://digitalgemology.com/gemstones/cubic-zirconia/emerald-cut)
- [Ruby](https://digitalgemology.com/gemstones/ruby/emerald-cut)
- [Sapphire](https://digitalgemology.com/gemstones/sapphire/emerald-cut)
- [Emerald](https://digitalgemology.com/gemstones/emerald/emerald-cut)
- [Amethyst](https://digitalgemology.com/gemstones/amethyst/emerald-cut)
- [Topaz](https://digitalgemology.com/gemstones/topaz/emerald-cut)
- [Spinel](https://digitalgemology.com/gemstones/spinel/emerald-cut)
- [Demantoid](https://digitalgemology.com/gemstones/demantoid/emerald-cut)
- [Zircon](https://digitalgemology.com/gemstones/zircon/emerald-cut)
- [Tourmaline](https://digitalgemology.com/gemstones/tourmaline/emerald-cut)
- [Peridot](https://digitalgemology.com/gemstones/peridot/emerald-cut)
- [Tanzanite](https://digitalgemology.com/gemstones/tanzanite/emerald-cut)
- [YAG](https://digitalgemology.com/gemstones/yag/emerald-cut)
- [Pyrope](https://digitalgemology.com/gemstones/pyrope/emerald-cut)
- [Almandine](https://digitalgemology.com/gemstones/almandine/emerald-cut)
- [Spessartine](https://digitalgemology.com/gemstones/spessartine/emerald-cut)
- [Grossular](https://digitalgemology.com/gemstones/grossular/emerald-cut)
- [Chrysoberyl](https://digitalgemology.com/gemstones/chrysoberyl/emerald-cut)
- [Kunzite](https://digitalgemology.com/gemstones/kunzite/emerald-cut)
- [Morganite](https://digitalgemology.com/gemstones/morganite/emerald-cut)
- [GGG](https://digitalgemology.com/gemstones/ggg/emerald-cut)
- [Strontium titanate](https://digitalgemology.com/gemstones/strontium-titanate/emerald-cut)
- [Synthetic rutile](https://digitalgemology.com/gemstones/synthetic-rutile/emerald-cut)