What Every Line on Your Certificate Means
Every IGI certified diamond at Bijolina comes with an independent grading report. This report is your diamond's identity document — it tells you exactly what you are buying. Here is what each section means and why it matters.
Report Header
- Report Number: A unique identification number for your specific diamond. This number is laser-inscribed on the diamond's girdle (the thin edge) for matching
- Report Date: When the diamond was examined and graded by IGI
- Report Type: Usually "Diamond Report" or "Laboratory Grown Diamond Report." Lab-grown diamonds are clearly identified on the report
Shape and Cutting Style
- Describes the diamond's shape (Round, Oval, Cushion, etc.) and its faceting arrangement (Brilliant, Step, Mixed)
- Round Brilliant is the most common. Emerald and Asscher are Step cuts. Radiant and Cushion are Modified Brilliant or Mixed
The 4Cs Section
- Carat Weight: The diamond's weight, measured to the hundredth decimal (e.g., 1.52 ct). This is an objective measurement, not an estimate. One carat = 0.2 grams
- Color Grade: D (colorless) through Z (light yellow/brown). D-F are colorless, G-J are near-colorless. Most people cannot distinguish between adjacent color grades without side-by-side comparison
- Clarity Grade: FL (Flawless) through I3 (Included). The grade indicates the severity of inclusions under 10x magnification. VS2 and above are "eye-clean" — inclusions invisible to the naked eye
- Cut Grade: Excellent, Very Good, Good, Fair, Poor. The most important grade for sparkle. Always choose Excellent
Proportions Section
- Measurements: Physical dimensions in millimeters (length x width x depth)
- Table %: Width of the top flat facet relative to total width
- Depth %: Total height relative to total width
- Crown Angle/Height: Upper facet geometry
- Pavilion Angle/Depth: Lower facet geometry
- Girdle: Thickness of the edge (Thin to Thick). Medium is ideal
- Culet: The bottom point. Should be "None" or "Pointed" for best appearance
Polish and Symmetry
- Polish: Quality of the surface finish. Excellent means no visible polish marks under 10x
- Symmetry: How precisely the facets are aligned. Excellent means near-perfect alignment
- Triple Excellent: Excellent Cut + Excellent Polish + Excellent Symmetry = the highest designation
Fluorescence
- Whether the diamond glows under ultraviolet light. Ranges from None to Very Strong Blue. None or Faint is most desirable. Strong fluorescence can sometimes cause a hazy appearance
Inscription
- The report number is laser-inscribed on the girdle. You can verify your diamond matches its certificate by checking this inscription under magnification