--- title: "DG-Octagonal Kite Spinel: Pros, Cons and Scores" description: "DG-Octagonal Kite in spinel: brilliance 71, fire 38, leakage 28%, 0 pros and 4 cons against the T73, from our ray-traced light census." url: https://digitalgemology.com/gemstones/spinel/dg-octagonal-kite image: https://digitalgemology.com/img/stone-cuts/dg-octagonal-kite-spinel-og.jpg?v=0f32ab15 --- > Markdown copy of https://digitalgemology.com/gemstones/spinel/dg-octagonal-kite. 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 # DG-Octagonal Kite Spinel: what our light census measures **Buy (instant download, personal-use license):** [DG-Octagonal Kite Cut 3D files, €14.99 · Personal use](https://digitalgemology.lemonsqueezy.com/checkout/buy/7f8bb426-65ee-4e34-a5ca-8afca2cfd900) · [DG-Octagonal Kite Cut cutting files, €12.99 · Personal use](https://digitalgemology.lemonsqueezy.com/checkout/buy/25afd253-e939-428f-b41c-144509a92281) · [Get the cube free](https://digitalgemology.lemonsqueezy.com/checkout/buy/2d1ab55f-2bd6-4897-a4cd-f3320f54e99e) Brilliance 71 · Fire 38 · Scintillation 60 · in our census, where the T73 scores 94 · 47 · 80 in spinel How the DG-Octagonal Kite handles light in spinel, measured: brilliance 71, fire 38 and 28% leakage, set against the T73 in the same stone and against the same cut in diamond. [Get the files](https://digitalgemology.com/gemstones/spinel/dg-octagonal-kite#buy) [Open it in the Simulator](https://digitalgemology.com/tools/3d_gemstone_simulator?cut=dg-octagonal-kite&stone=spinel&ct=1.00&view=angle&lighting=studio&turn=0) [All cuts in spinel](https://digitalgemology.com/gemstones/spinel) Light Return map of the DG-Octagonal Kite in spinel, face-up, from our own tracer at refractive index 1.712. Red, green and blue return light to the eye; gray leaks. ## DG-Octagonal Kite Spinel Spinel has a refractive index of 1.712 to 1.747 and a dispersion of 0.020. Its critical angle, from the low end of that range, is 35.7°, so a round design needs a pavilion of at least 36.1° for head-on light to reflect off both sides of the pavilion and leave through the table. We trace it with one index, 1.730, the midpoint of the published range, and a fire spread of 0.017, 0.86 of the published dispersion. Every picture here is our Light Return tracer at 1.712, and every figure is from the same light census that scores the other gemstones; the 3D Gemstone Simulator shows the DG-Octagonal Kite in spinel live. The DG-Octagonal Kite has 41 facets, a table of 55.0% of its width and a total depth of 70.0% of its width; its pavilion mains sit at 43.0°. In spinel, the census returns 71 of 100 for brilliance and 38 for fire, against 94 and 47 for the T73, our benchmark, in the same stone; the same DG-Octagonal Kite in diamond reads 88 and 82. ## Is spinel good in a DG-Octagonal Kite? Pros and cons, measured ### Pros No figure ahead by our thresholds ### Cons - [Less fire in spinel than in diamond](https://digitalgemology.com/gemstones/spinel/dg-octagonal-kite#con-fire) 38 vs 82 - [Returns less light than the T73 in spinel](https://digitalgemology.com/gemstones/spinel/dg-octagonal-kite#con-brilliance) 71 vs 94 - [Leaks more light than the T73 in spinel](https://digitalgemology.com/gemstones/spinel/dg-octagonal-kite#con-leak) 28 vs 6 - [Fewer facets, less sparkle](https://digitalgemology.com/gemstones/spinel/dg-octagonal-kite#con-scint) 60 vs 80 Compared with the T73 Round Brilliant in spinel and with the DG-Octagonal Kite 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 DG-Octagonal Kite in spinel (white) against the T73 Round Brilliant in spinel (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 spinel: ahead on 1, level on 1, behind on 6. - Global 70, the comparison 81, difference −11 - Brilliance 71, the comparison 94, difference −23 - Fire 38, the comparison 47, difference −9 - Scintillation 60, the comparison 80, difference −20 - Spread 96, the comparison 100, difference −4 - Symmetry 100, the comparison 100, difference 0 - Shape-norm 83, the comparison 101, difference −18 - Tilt 94, the comparison 75, difference +19 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=dg-octagonal-kite&stone=spinel); these are the same census figures as our [Cut Performance Index](https://digitalgemology.com/learn/cut-performance-index). ## What the DG-Octagonal Kite gains in spinel Against the T73 in spinel and the same cut in diamond, no figure of the DG-Octagonal Kite is ahead by the thresholds above. Its figures are in the wheel and the FAQ; [Spinel](https://digitalgemology.com/gemstones/spinel) ranks every cut we score in spinel. ## What the DG-Octagonal Kite gives up in spinel ### Less fire in spinel than in diamond **Fire 38** against 82 for the DG-Octagonal Kite in diamond: 44 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 (0.017 in spinel) and counts a ray as fire when the two directions differ by more than 0.6°. The DG-Octagonal Kite reads 38 against 82 for the same cut in diamond. The figure is the census's; the 3D Gemstone Simulator renders spinel'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=dg-octagonal-kite&stone=spinel&ct=1.00&view=up&lighting=sun&turn=0): the DG-Octagonal Kite in spinel under the sunny-day lighting. **What helps:** [the DG-Elongated Hexagon](https://digitalgemology.com/gemstones/spinel/dg-elongated-hexagon) reads 80 for fire in spinel, 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=dg-octagonal-kite&stone=spinel&ct=1.00&view=up&lighting=sun&turn=0) ### Returns less light than the T73 in spinel **Brilliance 71** against 94 for the T73 Round Brilliant in spinel: 23 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 spinel, whose critical angle is 35.7°, the DG-Octagonal Kite returns 71 of 100 and the T73 94. The DG-Octagonal Kite's pavilion mains sit at 43.0°, the T73's at 40.8°. The maps below show where each stone's light returns from and where it leaks. DG-Octagonal Kite in spinel · Brilliance 71 T73 Round Brilliant in spinel · Brilliance 94 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/spinel/dg-m5) reads 100 for brilliance in spinel, 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=dg-octagonal-kite&stone=spinel&ct=1.00&view=up&map=1&turn=0) ### Leaks more light than the T73 in spinel **Leakage 28** against 6 for the T73 Round Brilliant in spinel: 22 points higher Leakage is the share of the census rays that enter the stone and leave through the pavilion, or through the crown heading down. The DG-Octagonal Kite leaks 28% in spinel against 6% for the T73 in spinel. Grey in the maps below is leaking light; the share under each picture is that picture's own. DG-Octagonal Kite in spinel · Leakage 28 0° · 28% leak 10° · 27% leak 20° · 30% leak 30° · 39% leak T73 Round Brilliant in spinel · Leakage 6 0° · 0% leak 10° · 15% leak 20° · 30% leak 30° · 32% leak 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 DG-M5](https://digitalgemology.com/gemstones/spinel/dg-m5) reads 0% for leakage in spinel, the best of the cuts we score there. [Try it yourself: Tilt it yourself in the simulator's light map](https://digitalgemology.com/tools/3d_gemstone_simulator?cut=dg-octagonal-kite&stone=spinel&ct=1.00&view=up&map=1&turn=0) ### Fewer facets, less sparkle **Scintillation 60** against 80 for the T73 Round Brilliant in spinel: 20 points lower Scintillation follows the number of facets the stone shows: 100 × (1 − e^(−facets / 45)). The DG-Octagonal Kite has 41 facets and the T73 73, so 60 against 80. It depends on the geometry alone, so it is the same in every stone. *Facet diagram of the DG-Octagonal Kite: its crown, seen face-up, 41 facets in all* DG-Octagonal Kite · 41 facets · Scintillation 60 *Facet diagram of the T73 Round Brilliant: its crown, seen face-up, 73 facets in all* T73 Round Brilliant · 73 facets · Scintillation 80 Scintillation follows the number of facets: more facets, more and smaller flashes as the stone moves. Compare the facet counts under the drawings; each drawing shows only the crown. Drawn from each cut's own model. **What helps:** [the DG-Miliano](https://digitalgemology.com/gemstones/spinel/dg-miliano) reads 98 for scintillation in spinel, the best of the cuts we score there. [Try it yourself: Compare the Scintillation spoke in the Cut Performance Wheel](https://digitalgemology.com/tools/cut-performance-wheel?cut=dg-octagonal-kite&stone=spinel) ## Our verdict on the DG-Octagonal Kite in spinel Against the T73 in spinel and the same cut in diamond, no figure of the DG-Octagonal Kite is ahead by our thresholds. The catch: it shows less fire than in diamond, returns less light than the T73, leaks more light than the T73 and has fewer facets to sparkle with. If that catch matters more to you, [the DG-Elongated Hexagon](https://digitalgemology.com/gemstones/spinel/dg-elongated-hexagon) reads 80 for fire in spinel, 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 DG-Octagonal Kite model we traced. ## DG-Octagonal Kite Spinel: questions ### Is the DG-Octagonal Kite a good cut for spinel? In our census the DG-Octagonal Kite returns 71 of 100 for brilliance and 38 for fire in spinel, against 94 and 47 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. ### What pavilion angle does spinel need? At least 36.1° for a round design: spinel's critical angle is 35.7°, 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 DG-Octagonal Kite's pavilion mains sit at 43.0°. ### How much does a DG-Octagonal Kite weigh in spinel? At 6.5 mm across, 1.28 ct in spinel, against 1.25 ct for the same cut in diamond (+3%): spinel's specific gravity is 3.62, diamond's 3.52. ### Can I see the DG-Octagonal Kite in spinel in 3D? Yes: the 3D Gemstone Simulator renders it live, with spinel's own refractive index and dispersion. Spinel 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 DG-Octagonal Kite Cut files *6 formats* *Millimeters* *Watertight* ### DG-Octagonal Kite Cut 3D files The DG-Octagonal Kite Cut as exact geometry: 41 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 €14.99 · [Personal use](https://digitalgemology.com/licence) [Buy the 3D files](https://digitalgemology.lemonsqueezy.com/checkout/buy/7f8bb426-65ee-4e34-a5ca-8afca2cfd900) *GemCad* *96 index* ### DG-Octagonal Kite Cut cutting files The DG-Octagonal Kite Cut as a faceting design: 33 + 8 girdles = 41 facets, 96 index, 8-fold mirror-image symmetry, ready for the machine. - **.asc** GemCad design file, 96 index gear - **.csv** Tier table: angles, indices and cutting order - **Diagram** Printable faceting diagram €12.99 · [Personal use](https://digitalgemology.com/licence) [Buy the cutting files](https://digitalgemology.lemonsqueezy.com/checkout/buy/25afd253-e939-428f-b41c-144509a92281) 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 [Spinel: optical properties and the top ten cuts](https://digitalgemology.com/gemstones/spinel) · [The DG-Octagonal Kite: specifications, model and files](https://digitalgemology.com/cuts/dg-octagonal-kite) ### Other cuts in spinel - [T73 Round Brilliant](https://digitalgemology.com/gemstones/spinel/t73-round-brilliant) - [T105 Round Brilliant](https://digitalgemology.com/gemstones/spinel/t105-round-brilliant) - [DG-Vitruvio](https://digitalgemology.com/gemstones/spinel/dg-vitruvio) - [DG-Anteros](https://digitalgemology.com/gemstones/spinel/dg-anteros) - [DG-Broken Hearts and Arrows](https://digitalgemology.com/gemstones/spinel/dg-broken-hearts-and-arrows) - [Baguette Cut](https://digitalgemology.com/gemstones/spinel/baguette) - [Emerald Cut](https://digitalgemology.com/gemstones/spinel/emerald-cut) - [Marquise Cut](https://digitalgemology.com/gemstones/spinel/marquise) - [Oval Cut](https://digitalgemology.com/gemstones/spinel/oval) - [Pear Cut](https://digitalgemology.com/gemstones/spinel/pear) - [Radiant Cut](https://digitalgemology.com/gemstones/spinel/radiant) - [Rectangle Cut](https://digitalgemology.com/gemstones/spinel/rectangle) - [Teardrop Cut](https://digitalgemology.com/gemstones/spinel/teardrop) - [Asscher Cut](https://digitalgemology.com/gemstones/spinel/asscher) - [Cushion Cut](https://digitalgemology.com/gemstones/spinel/cushion) - [Emerald Square Cut](https://digitalgemology.com/gemstones/spinel/emerald-square) - [Princess Cut](https://digitalgemology.com/gemstones/spinel/princess) - [Radiant Square Cut](https://digitalgemology.com/gemstones/spinel/radiant-square) - [Square Cut](https://digitalgemology.com/gemstones/spinel/square) - [Triangle Cut](https://digitalgemology.com/gemstones/spinel/triangle) - [Trilliant Cut](https://digitalgemology.com/gemstones/spinel/trilliant) - [Trillion Cut](https://digitalgemology.com/gemstones/spinel/trillion) - [Hexagon Cut](https://digitalgemology.com/gemstones/spinel/hexagon) - [Octagon Cut](https://digitalgemology.com/gemstones/spinel/octagon) - [Portuguese Bird's Nest Cut](https://digitalgemology.com/gemstones/spinel/portuguese-birds-nest) - [Old Single Cut](https://digitalgemology.com/gemstones/spinel/old-single) - [Mazarin Cut](https://digitalgemology.com/gemstones/spinel/mazarin) - [Peruzzi Cut](https://digitalgemology.com/gemstones/spinel/peruzzi) - [Old Mine Cut](https://digitalgemology.com/gemstones/spinel/old-mine) - [Old European Cut](https://digitalgemology.com/gemstones/spinel/old-european) - [T57 Round Brilliant](https://digitalgemology.com/gemstones/spinel/t57-round-brilliant) - [DG-M5](https://digitalgemology.com/gemstones/spinel/dg-m5) - [DG-Miliano](https://digitalgemology.com/gemstones/spinel/dg-miliano) - [DG-Rafaello](https://digitalgemology.com/gemstones/spinel/dg-rafaello) - [DG-Bowtie](https://digitalgemology.com/gemstones/spinel/dg-bowtie) - [DG-Elongated Hexagon](https://digitalgemology.com/gemstones/spinel/dg-elongated-hexagon) ### The DG-Octagonal Kite in other gemstones - [Diamond](https://digitalgemology.com/gemstones/diamond/dg-octagonal-kite) - [Moissanite](https://digitalgemology.com/gemstones/moissanite/dg-octagonal-kite) - [Cubic Zirconia](https://digitalgemology.com/gemstones/cubic-zirconia/dg-octagonal-kite) - [Ruby](https://digitalgemology.com/gemstones/ruby/dg-octagonal-kite) - [Sapphire](https://digitalgemology.com/gemstones/sapphire/dg-octagonal-kite) - [Emerald](https://digitalgemology.com/gemstones/emerald/dg-octagonal-kite) - [Amethyst](https://digitalgemology.com/gemstones/amethyst/dg-octagonal-kite) - [Topaz](https://digitalgemology.com/gemstones/topaz/dg-octagonal-kite) - [Demantoid](https://digitalgemology.com/gemstones/demantoid/dg-octagonal-kite) - [Zircon](https://digitalgemology.com/gemstones/zircon/dg-octagonal-kite) - [Tourmaline](https://digitalgemology.com/gemstones/tourmaline/dg-octagonal-kite) - [Peridot](https://digitalgemology.com/gemstones/peridot/dg-octagonal-kite) - [Tanzanite](https://digitalgemology.com/gemstones/tanzanite/dg-octagonal-kite) - [YAG](https://digitalgemology.com/gemstones/yag/dg-octagonal-kite) - [Pyrope](https://digitalgemology.com/gemstones/pyrope/dg-octagonal-kite) - [Almandine](https://digitalgemology.com/gemstones/almandine/dg-octagonal-kite) - [Spessartine](https://digitalgemology.com/gemstones/spessartine/dg-octagonal-kite) - [Grossular](https://digitalgemology.com/gemstones/grossular/dg-octagonal-kite) - [Chrysoberyl](https://digitalgemology.com/gemstones/chrysoberyl/dg-octagonal-kite) - [Kunzite](https://digitalgemology.com/gemstones/kunzite/dg-octagonal-kite) - [Iolite](https://digitalgemology.com/gemstones/iolite/dg-octagonal-kite) - [Morganite](https://digitalgemology.com/gemstones/morganite/dg-octagonal-kite) - [GGG](https://digitalgemology.com/gemstones/ggg/dg-octagonal-kite) - [Strontium titanate](https://digitalgemology.com/gemstones/strontium-titanate/dg-octagonal-kite) - [Synthetic rutile](https://digitalgemology.com/gemstones/synthetic-rutile/dg-octagonal-kite)