DG-Broken Hearts and Arrows Spinel: Pros, Cons and Scores

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-Broken Hearts and Arrows in spinel live.

The DG-Broken Hearts and Arrows has 89 facets, a table of 53.0% of its width and a total depth of 61.7% of its width; its pavilion mains sit at 40.8°. In spinel, the census returns 95 of 100 for brilliance and 45 for fire, against 94 and 47 for the T73, our benchmark, in the same stone; the same DG-Broken Hearts and Arrows in diamond reads 93 and 78.

Is spinel good in a DG-Broken Hearts and Arrows? Pros and cons, measured

Pros

More facets, more sparkle 86 vs 80

Cons

Less fire in spinel than in diamond 45 vs 78
Loses more light when tilted than in diamond 74 vs 93
Leaks more in spinel than in diamond 5 vs 2

Compared with the T73 Round Brilliant in spinel and with the DG-Broken Hearts and Arrows 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.

All eight scores against the T73

At a glance: the DG-Broken Hearts and Arrows 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 3, level on 2, behind on 3.

Global81, the comparison 81, difference 0
Brilliance95, the comparison 94, difference +1
Fire45, the comparison 47, difference −2
Scintillation86, the comparison 80, difference +6
Spread100, the comparison 100, difference 0
Symmetry99, the comparison 100, difference −1
Shape-norm102, the comparison 101, difference +1
Tilt74, the comparison 75, difference −1

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; these are the same census figures as our Cut Performance Index.

What the DG-Broken Hearts and Arrows gains in spinel

More facets, more sparkle

Scintillation 86 against 80 for the T73 Round Brilliant in spinel: 6 points higher

Scintillation follows the number of facets the stone shows: 100 × (1 − e^(−facets / 45)). The DG-Broken Hearts and Arrows has 89 facets and the T73 73, so 86 against 80. It depends on the geometry alone, so it is the same in every stone.

DG-Broken Hearts and Arrows · 89 facets · Scintillation 86

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.

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

What the DG-Broken Hearts and Arrows gives up in spinel

Less fire in spinel than in diamond

Fire 45 against 78 for the DG-Broken Hearts and Arrows in diamond: 33 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-Broken Hearts and Arrows reads 45 against 78 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: the DG-Broken Hearts and Arrows in spinel under the sunny-day lighting.

What helps: the 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

Loses more light when tilted than in diamond

Tilt 74 against 93 for the DG-Broken Hearts and Arrows in diamond: 19 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 DG-Broken Hearts and Arrows keeps 74 against 93 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.

Dg-broken hearts and arrows in spinel tilted 0 degrees: Light Return map, 0% 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; gray is leakage. The share under each frame is that picture's own.

Dg-broken hearts and arrows in spinel tilted 10 degrees: Light Return map, 14% 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; gray is leakage. The share under each frame is that picture's own.

What helps: the DG-Miliano reads 82 for tilt in spinel, the best of the cuts we score there.

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

Leaks more in spinel than in diamond

Leakage 5 against 2 for the DG-Broken Hearts and Arrows in diamond: 3 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-Broken Hearts and Arrows leaks 5% in spinel against 2% for the same cut in diamond. Grey in the maps below is leaking light; the share under each picture is that picture's own.

What helps: the 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

Our verdict on the DG-Broken Hearts and Arrows in spinel

Pick the DG-Broken Hearts and Arrows in spinel for this: it has more facets to sparkle with. The catch: it shows less fire than in diamond, loses more light when tilted than in diamond and leaks more than in diamond.

If that catch matters more to you, the 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-Broken Hearts and Arrows model we traced.

DG-Broken Hearts and Arrows Spinel: questions

Is the DG-Broken Hearts and Arrows a good cut for spinel?

In our census the DG-Broken Hearts and Arrows returns 95 of 100 for brilliance and 45 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 1 pro and 3 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-Broken Hearts and Arrows's pavilion mains sit at 40.8°.

How much does a DG-Broken Hearts and Arrows weigh in spinel?

At 6.5 mm across, 1.04 ct in spinel, against 1.01 ct for the same cut in diamond (+3%): spinel's specific gravity is 3.62, diamond's 3.52.

Can I see the DG-Broken Hearts and Arrows 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-Broken Hearts and Arrows Cut files

6 formatsMillimetersWatertight

DG-Broken Hearts and Arrows Cut 3D files

The DG-Broken Hearts and Arrows Cut as exact geometry: 89 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 modeling and rendering
FBXBlender, 3ds Max, Maya, Cinema 4D, Unity, Unreal
GLBWeb, AR and quick previews

€14.99 · Personal useBuy the 3D files

GemCad96 index

DG-Broken Hearts and Arrows Cut cutting files

The DG-Broken Hearts and Arrows Cut as a faceting design: 73 + 16 girdles = 89 facets, 96 index, 8-fold mirror-image symmetry, ready for the machine.

.ascGemCad design file, 96 index gear
.csvTier table: angles, indices and cutting order
DiagramPrintable faceting diagram

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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).

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DG-Broken Hearts and Arrows Spinel: more facets, more sparkle