IGI report LG783622611
1.51 ct Marquise Laboratory-Grown Diamond
89/100 · Refined
A strong candidate on paper; confirm its light pattern in imagery.
What reads well
- A 2.09:1 length-to-width ratio sits in the classic marquise range.
- Face-up spread (12.28 × 5.88 mm) is typical or better for a 1.51 ct marquise.
- F color is in the colorless range.
- VVS2 clarity: inclusions are not a practical visual factor.
- No fluorescence: no haze risk to weigh.
What deserves a closer look
- A 64.5% depth is on the deep side for a marquise; deeper pavilions are associated with a stronger bow-tie and hidden weight.
- Screening only: for this marquise, check images or video of the exact stone for the bow-tie and whether the two points line up end to end.
- Treatment status is not stated on the report. For a laboratory-grown diamond, ask whether it is as-grown or post-growth treated.
The reading, field by field
- Table · Ideal
- At 59%, the table sits within the typical 53–63% range for a marquise, balancing brightness with fire.
- Total depth · Closer look
- 64.5% is deeper than typical for a marquise (58–64%). Extra depth holds weight below the girdle, so the stone can face up smaller than its carat weight suggests and may show a stronger bow-tie.
- Length-to-width · Ideal
- A 2.09:1 outline is within the classic 1.85–2.2:1 range for a marquise.
- Polish · Ideal
- Excellent polish is the top finish grade — facets are cleanly executed with nothing that would soften sparkle.
- Symmetry · Favorable
- Very Good symmetry is a fine result; the difference from Excellent is rarely visible without magnification.
- Girdle · Ideal
- Medium To Slightly Thick (Faceted): a durable girdle thickness that doesn't hide meaningful weight.
- Culet · Ideal
- Pointed: no visible culet facet when viewed face-up.
- Color · Ideal
- F is in the colorless range and faces up white in any metal.
- Clarity · Ideal
- VVS2: inclusions, if any, are only visible under magnification.
- Fluorescence · Ideal
- None: no meaningful effect on appearance.
What to check on the exact stone
- With 64.5% depth, does this stone face up smaller than a typical 1.51 ct marquise?
- In a face-up video, does the bow-tie flicker as the stone tilts, or stay a fixed dark band across the center?
- Will the ring setting use protective V-tip prongs or a bezel to safeguard the two delicate points?
- Can you show me the inscribed report number under a loupe before it is set?
Report facts
- Origin
- Laboratory-grown
- Carat
- 1.51 ct
- Shape
- Marquise
- Cut grade
- Not given for this shape
- Color
- F
- Clarity
- VVS2
- Measurements
- 12.28 × 5.88 × 3.79 mm
- Table
- 59%
- Total depth
- 64.5%
- Crown angle
- Not given for this shape
- Pavilion angle
- Not given for this shape
- Polish
- Excellent
- Symmetry
- Very Good
- Girdle
- Medium to slightly thick (faceted)
- Culet
- Pointed
- Fluorescence
- None