The Carat Standard

IGI report LG780694989

1.50 ct Round Brilliant Laboratory-Grown Diamond

90/100 · Refined

A strong, composed candidate on paper.

What reads well

  • The IGI Excellent cut grade corroborates the measured proportions.
  • Excellent polish and symmetry, the top finish grades.
  • E color is in the colorless range.
  • VS1 clarity is typically eye-clean in a round brilliant.
  • No fluorescence: no haze risk to weigh.

What deserves a closer look

  • 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 58%, the table sits within the typical 53–59% range for a round brilliant, balancing brightness with fire.
Total depth · Ideal
62.7% is within the typical 59.5–63% range for a round brilliant, keeping weight where it contributes to face-up size and light return.
Crown angle · Closer look
A 36.2° crown is steeper than the typical 32–36° zone. Steep crowns can add fire, but only pair well with a slightly shallower pavilion.
Pavilion angle · Closer look
40.4° is shallower than the narrow 40.5–41.3° zone. Shallow pavilions can let light pass straight through, looking glassy.
Polish · Ideal
Excellent polish is the top finish grade — facets are cleanly executed with nothing that would soften sparkle.
Symmetry · Ideal
Excellent symmetry is the top finish grade — facets are cleanly executed with nothing that would soften sparkle.
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
E is in the colorless range and faces up white in any metal.
Clarity · Favorable
VS1 is typically eye-clean.
Fluorescence · Ideal
None: no meaningful effect on appearance.
Cut grade · Ideal
Excellent as issued by IGI, on IGI's own scale. The measured proportions above tell you more than the label.

What to check on the exact stone

  • Does a gray ring or glassy patch show around the center when you look straight down?
  • Does this CVD diamond show any brown or gray undertone face-up in daylight?
  • Can you show me the inscribed report number under a loupe before it is set?

Report facts

Origin
Laboratory-grown
Carat
1.50 ct
Shape
Round Brilliant
Cut grade
Excellent (IGI)
Color
E
Clarity
VS1
Measurements
7.22–7.25 × 4.54 mm
Table
58%
Total depth
62.7%
Crown angle
36.2°
Pavilion angle
40.4°
Polish
Excellent
Symmetry
Excellent
Girdle
Medium to slightly thick (faceted)
Culet
Pointed
Fluorescence
None

About The Carat Standard Score

How The Carat Standard reads a report