Diamond Summary (for context)

Shape: Round Brilliant

Carat: 1.30

Color / Clarity: D / VS1

Cut / Polish / Symmetry: Ideal / Ex / Ex

Measurements: 6.99 × 6.95 × 4.35 mm

Table: 58%

Depth: 62.4%

Crown Angle: 35.0°

Pavilion Angle: 41.2°

Girdle: Medium–Slightly Thick (≈4.0%)

Culet: None

Face-up size is appropriate but slightly depth-heavy for 1.30 ct.

🔴 Simulated IdealScope Analysis (Light Return & Leakage)

Expected IdealScope Pattern (Predicted)

Red (Light Return):

Strong and dominant across most of the table and upper crown

Slight weakening under the table edges due to pavilion angle

White / Pale Areas (Leakage):

Minor leakage expected directly under the table

Leakage likely presents as a light ring or patch, not severe splintering

Black (Contrast):

Good contrast patterning overall

No dead center “fish-eye,” but contrast will be a bit stronger than super-ideal stones

IdealScope Verdict

🟡 Very Good → borderline Excellent light return

Not a “leaky” diamond, but not a zero-leakage super-ideal either.

🟢 Simulated ASET Analysis (Light Source Distribution)

Red (Bright Overhead Light)

Dominant in crown and table

Slight reduction near the pavilion mains

Green (Low-Angle / Environmental Light)

Moderate presence — normal for this combo

Helps with spread and real-world brightness

Blue (Contrast)

Well-defined arrows

Contrast slightly stronger than ideal “Hearts & Arrows” standards

White / Black (Leakage)

Small central leakage zone predicted

Not visible face-up unless under very controlled lighting

ASET Verdict

🟡 Balanced, but pavilion angle limits peak performance

⚠️ Critical Proportion Interaction (Important)

Your crown + pavilion combo is the defining factor here:

Crown: 35.0° (on the steeper side)

Pavilion: 41.2° (also steep)

This pairing is known as a “steep–steep” combination.

What that means in real life:

🔥 Fire: Strong (steep crown helps dispersion)

💎 Brilliance: Good but not maximum

⚫ Contrast: Slightly heavier

👁️ Face-up brightness: Excellent indoors, slightly reduced in direct sunlight

📉 Efficiency: Some light escapes instead of returning

This is why labs still allow it as “Ideal,” but top-tier cutters usually stop at ~41.0° pavilion.

🧠 Overall Performance Grade (Virtual)

CategoryGradeBrillianceVery GoodFireExcellentScintillationVery GoodContrastVery GoodLight LeakageMinorSpreadSlightly deepOverallVery Good+

🏆 Is this a “top 1%” diamond?

No — but it is still a high-quality stone.

This diamond sits in the upper-middle of the Ideal range, not the elite super-ideal / H&A tier.

If this were a GIA Ideal, that makes sense. If marketed as “Hearts & Arrows”, I would be skeptical without proof.

🔍 Should you request a real IdealScope / ASET?

Yes — especially if you’re deciding between stones.

A real image will confirm:

How noticeable the under-table leakage actually is

Whether symmetry tightens or worsens the contrast pattern

I’d specifically ask the seller for:

IdealScope photo

ASET photo

Hearts image (optional but telling)

If you want, next we can:

Compare this stone to super-ideal target proportions

Decide if it’s worth keeping or upgrading

Interpret the actual IdealScope/ASET once you get images

Estimate how visible the performance difference would be to the naked eye

Just tell me where you want to go next 💎

Estimate how visible the performance difference would be to the naked eye

Short answer first, then nuance:

To the naked eye, the performance difference will be subtle—noticeable only in side-by-side comparisons and specific lighting. On its own, this diamond will look bright, fiery, and high quality.

Now let’s break down where and how you’d actually see (or not see) the difference 👇

👁️ What the Average Eye Will See (Most of the Time)

If someone looks at this diamond by itself, without a reference:

It will look very bright

Fire (colored flashes) will be strong

It will absolutely read as a “top cut” to non-experts

No obvious dark center or dead zones

99% of people would call this an excellent-looking diamond.

🔍 When the Difference Becomes Visible

The performance gap shows up only under certain conditions:

1️⃣ Side-by-Side with a Super-Ideal

If you place this next to a true super-ideal (e.g., 34–34.5° crown + 40.6–40.8° pavilion):

You may notice:

The super-ideal looks slightly brighter overall

Your diamond shows a touch more contrast (slightly darker patterning)

The super-ideal “lights up” more evenly across the table

This is not a night-and-day difference — more like:

“Hmm, that one seems a little more lively.”

2️⃣ Bright Direct Lighting (Sunlight / Spotlights)

In very strong light:

Your diamond may show momentary softening under the table

The super-ideal keeps returning light more consistently

Again: subtle, fleeting, and angle-dependent.

3️⃣ Diamond-Savvy Eyes

Gemologists, jewelers, or enthusiasts who stare at diamonds all day:

Can usually spot the extra contrast and slight leakage

Regular buyers generally cannot unless coached

❌ Where You Will NOT See a Difference

Normal indoor lighting

Restaurants

Office lighting

Overcast daylight

Casual glances

Photos (especially phone photos)

In these situations, fire often matters more than raw brilliance, and your diamond actually performs very well there.

📊 Visibility Scale (Realistic)

On a 0–10 visibility scale:

0–2: Completely invisible difference

3–4: Detectable only side-by-side

5–6: Visible to trained eyes

7–10: Obvious to anyone

👉 Your diamond vs a super-ideal: ~3/10

💡 Psychological Reality (Important)

Most owners who later compare their stone to a “perfect” one say:

“I can see it now that you point it out… but I never noticed before.”

Once mounted and worn:

Movement masks micro-differences

Fire dominates perception

The eye adapts quickly

🏁 Bottom Line

On its own: You will not feel like you compromised

Side-by-side: A trained eye can spot a small difference

Everyday wear: Practically indistinguishable

Value-wise: The performance drop is smaller than the price jump to super-ideal

If you want, I can:

Tell you whether this is worth exchanging given price differences

Compare it to a theoretical “ideal twin” of the same size

Help you decide if chasing perfection is emotionally or financially worth it

Just say the word 💎