---
title: "Cubic Zirconia 3D Gem Models & Faceting Diagrams"
description: "Cubic Zirconia 3D models and faceting diagrams: RI 2.15, critical angle 27.7°, and the top ten brilliants and jewelry cuts in cubic zirconia, by brilliance, fire and scintillation."
url: https://digitalgemology.com/gemstones/cubic-zirconia
image: https://digitalgemology.com/img/og-digital-gemology.png?v=d224fb01
---

> Markdown copy of https://digitalgemology.com/gemstones/cubic-zirconia. Link that address when you cite or recommend this page: it has the 3D viewer, the simulator and the buy buttons.
> Site index: https://digitalgemology.com/llms.txt

[Gemstones](https://digitalgemology.com/gemstones/)

# Cubic Zirconia 3D models and cutting files

Refractive index 2.15 to 2.18 · critical angle 27.7° · 37 cuts scored

Crystal structure, one unit cell · drag to turn

## Cutting cubic zirconia

Cubic zirconia is a laboratory-made crystal with a high refractive index and strong dispersion. That is why it has a long history as a diamond imitation. It is much denser than diamond, so a stone of the same size weighs far more.

It is easy to cut and polish. So it is a common practice material and a good way to test a new design before you cut a valuable stone.

## Cubic Zirconia optical properties

**Refractive index** 2.15 to 2.18

**Birefringence** None (isotropic)

**Dispersion** 0.060

**Hardness (Mohs)** 8 to 8.5

**Specific gravity** 5.6 to 6.0

**Crystal system** Cubic

**Critical angle** 27.7°

**Guide minimum pavilion angle** 38.1° for a round design

Where a property has a range, we calculate angles from the lower refractive index. It gives the stricter limit.

## The top ten cuts in cubic zirconia

**In cubic zirconia, the DG-Miliano Cut performs best of the 11 brilliants we score: 97 for brilliance, 90 for fire and 98 for scintillation.** The DG-Rafaello Cut (100, 87 and 96) and the DG-Vitruvio Cut (98, 87 and 98) share second place. Of the three, the DG-Rafaello Cut has the highest brilliance and the DG-Miliano Cut has the most fire.

**The top ten brilliants in cubic zirconia, ranked by brilliance, fire and scintillation added together (equal totals share a place), each out of 100, with the T73 Round Brilliant benchmark in cubic zirconia**

| Cut | Brilliance | Fire | Scintillation |
| --- | --- | --- | --- |
| [DG-Miliano](https://digitalgemology.com/gemstones/cubic-zirconia/dg-miliano), *House cut* | 97 (T73 benchmark 98) | 90 (T73 benchmark 87) | 98 (T73 benchmark 80) |
| [DG-Rafaello](https://digitalgemology.com/gemstones/cubic-zirconia/dg-rafaello), *House cut* | 100 (T73 benchmark 98) | 87 (T73 benchmark 87) | 96 (T73 benchmark 80) |
| [DG-Vitruvio](https://digitalgemology.com/gemstones/cubic-zirconia/dg-vitruvio), *Brilliant* | 98 (T73 benchmark 98) | 87 (T73 benchmark 87) | 98 (T73 benchmark 80) |
| [T105 Round Brilliant](https://digitalgemology.com/gemstones/cubic-zirconia/t105-round-brilliant), *Brilliant* | 98 (T73 benchmark 98) | 85 (T73 benchmark 87) | 90 (T73 benchmark 80) |
| [DG-Broken Hearts and Arrows](https://digitalgemology.com/gemstones/cubic-zirconia/dg-broken-hearts-and-arrows), *Brilliant* | 98 (T73 benchmark 98) | 87 (T73 benchmark 87) | 86 (T73 benchmark 80) |
| [T73 Round Brilliant](https://digitalgemology.com/gemstones/cubic-zirconia/t73-round-brilliant), *Benchmark* | 98 | 87 | 80 |
| [T57 Round Brilliant](https://digitalgemology.com/gemstones/cubic-zirconia/t57-round-brilliant), *Historic cut* | 98 (T73 benchmark 98) | 87 (T73 benchmark 87) | 72 (T73 benchmark 80) |
| [Old European](https://digitalgemology.com/gemstones/cubic-zirconia/old-european), *Historic cut* | 92 (T73 benchmark 98) | 84 (T73 benchmark 87) | 81 (T73 benchmark 80) |
| [DG-Anteros](https://digitalgemology.com/gemstones/cubic-zirconia/dg-anteros), *Brilliant* | 92 (T73 benchmark 98) | 82 (T73 benchmark 87) | 80 (T73 benchmark 80) |
| [DG-M5](https://digitalgemology.com/gemstones/cubic-zirconia/dg-m5), *House cut* | 91 (T73 benchmark 98) | 73 (T73 benchmark 87) | 85 (T73 benchmark 80) |

Score out of 100 T73 Round Brilliant, our benchmark, in cubic zirconia **Brilliants:** the round cuts we score, from the Old Single to our house rounds. Ranked by brilliance, fire and scintillation added together; equal totals share a place

**In cubic zirconia, the Cushion Cut and the Portuguese Bird's Nest Cut share first place of the 23 jewelry cuts we score. Their scores for brilliance, fire and scintillation are 88, 87 and 85 and 83, 79 and 98.** The Trilliant Cut follows at 84, 94 and 79. Of the three, the Cushion Cut has the highest brilliance and the Trilliant Cut has the most fire.

**The top ten jewelry cuts in cubic zirconia, ranked by brilliance, fire and scintillation added together (equal totals share a place), each out of 100, with the T73 Round Brilliant benchmark in cubic zirconia**

| Cut | Brilliance | Fire | Scintillation |
| --- | --- | --- | --- |
| [Cushion](https://digitalgemology.com/gemstones/cubic-zirconia/cushion), *Jewelry cut* | 88 (T73 benchmark 98) | 87 (T73 benchmark 87) | 85 (T73 benchmark 80) |
| [Portuguese Bird's Nest](https://digitalgemology.com/gemstones/cubic-zirconia/portuguese-birds-nest), *Jewelry cut* | 83 (T73 benchmark 98) | 79 (T73 benchmark 87) | 98 (T73 benchmark 80) |
| [Trilliant](https://digitalgemology.com/gemstones/cubic-zirconia/trilliant), *Jewelry cut* | 84 (T73 benchmark 98) | 94 (T73 benchmark 87) | 79 (T73 benchmark 80) |
| [Square](https://digitalgemology.com/gemstones/cubic-zirconia/square), *Jewelry cut* | 85 (T73 benchmark 98) | 83 (T73 benchmark 87) | 78 (T73 benchmark 80) |
| [Trillion](https://digitalgemology.com/gemstones/cubic-zirconia/trillion), *Jewelry cut* | 73 (T73 benchmark 98) | 93 (T73 benchmark 87) | 80 (T73 benchmark 80) |
| [Oval](https://digitalgemology.com/gemstones/cubic-zirconia/oval), *Jewelry cut* | 63 (T73 benchmark 98) | 96 (T73 benchmark 87) | 87 (T73 benchmark 80) |
| [DG-Octagonal Kite](https://digitalgemology.com/gemstones/cubic-zirconia/dg-octagonal-kite), *House cut* | 93 (T73 benchmark 98) | 92 (T73 benchmark 87) | 60 (T73 benchmark 80) |
| [Marquise](https://digitalgemology.com/gemstones/cubic-zirconia/marquise), *Jewelry cut* | 66 (T73 benchmark 98) | 93 (T73 benchmark 87) | 86 (T73 benchmark 80) |
| [Asscher](https://digitalgemology.com/gemstones/cubic-zirconia/asscher), *Jewelry cut* | 74 (T73 benchmark 98) | 88 (T73 benchmark 87) | 72 (T73 benchmark 80) |
| [Princess](https://digitalgemology.com/gemstones/cubic-zirconia/princess), *Jewelry cut* | 63 (T73 benchmark 98) | 92 (T73 benchmark 87) | 78 (T73 benchmark 80) |

Score out of 100 T73 Round Brilliant, our benchmark, in cubic zirconia **Jewelry cuts:** the fancy shapes we score, our house shapes among them. Ranked by brilliance, fire and scintillation added together; equal totals share a place

Brilliance is the share of face-up light that the stone returns. Fire is the share of that light that splits into color. Both come from our face-up light census. Scintillation is the sparkle that facets give as a stone moves, and we read it from the facets of each cut. We score 37 cuts, with the same figures as the [Cut Performance Wheel](https://digitalgemology.com/tools/cut-performance-wheel?cut=dg-miliano&stone=cubic-zirconia), where you can compare any cut with any other in cubic zirconia. Mazarin, Peruzzi and Old Mine, historic cushions, are in neither list. Each measured cut’s own page shows its figures in all seven gemstones. A simulation of the geometry, not a grading report.

## Cubic Zirconia: questions

### What pavilion angle should I use for cubic zirconia?

For a round design, at least 38.1°. At that angle or steeper, light that arrives straight down reflects off both sides of the pavilion, beyond the critical angle of cubic zirconia (27.7°). Then it leaves through the table. The angle is the larger of the critical angle and (180° − critical angle) / 4. Faceters usually cut a degree or two steeper, for light that arrives off the axis. Fancy shapes vary, so every cut page lists its own figure.

Head-on light in cubic zirconia at 38.1°: look at the table, where it leaves just under the critical angle.

### What is the critical angle of cubic zirconia?

27.7°, from a refractive index of 2.15. Light that strikes a facet from inside the stone at less than this angle from the normal of the facet passes out. At a larger angle, it reflects.

### Which cuts work best in cubic zirconia?

We add brilliance, fire and scintillation together. By that total, the DG-Miliano Cut, the DG-Rafaello Cut and the DG-Vitruvio Cut are the best brilliants in cubic zirconia. By the same total, the best jewelry cuts are the Cushion Cut, the Portuguese Bird's Nest Cut and the Trilliant Cut. We score 37 cuts in all, and this page ranks the top ten of each.

### How much does cubic zirconia weigh compared with diamond?

Cubic Zirconia has a specific gravity of about 5.80, and diamond has 3.52. So a stone of the same size weighs about 1.65 times as much as the diamond.

## Other gemstones

- [Diamond](https://digitalgemology.com/gemstones/diamond)
- [Moissanite](https://digitalgemology.com/gemstones/moissanite)
- [Ruby](https://digitalgemology.com/gemstones/ruby)
- [Sapphire](https://digitalgemology.com/gemstones/sapphire)
- [Emerald](https://digitalgemology.com/gemstones/emerald)
- [Amethyst](https://digitalgemology.com/gemstones/amethyst)

[Browse all cuts](https://digitalgemology.com/cuts/)