How to Read a Diamond Certificate

Every certified diamond tells a story written on its grading certificate.
At BÄL DIAMONDS, every stone above 1.00ct comes with an independent lab certificate from IGI or GIA, proving its authenticity, quality, and origin.

Here’s how to read your certificate like an expert.

Understanding the Diamond Certificate Layout

Every report contains key data fields here’s how to interpret them:

Certificate Number

A unique ID engraved on the diamond’s girdle.
You can verify it on the laboratory’s official website (IGI.net or GIA.edu).
At BÄL, we include this number in your purchase documentation for traceability.

Shape & Cutting Style

Indicates the diamond’s shape (Round, Oval, Cushion, Pear, etc.) and its faceting pattern.
Example: Round Brilliant Cut or Emerald Step Cut.

Related: Choose Your Diamond Shape

Measurements

Shows the diamond’s dimensions in millimeters important for understanding proportions and setting compatibility.
Example: 6.50 – 6.55 × 3.95 mm.

Tip: Cross-check with our Carat-to-mm Conversion Chart

Carat Weight

Indicates how much the diamond weighs.
1 carat = 0.2 grams.
Because it’s measured precisely to the hundredth, two diamonds may have the same carat but look slightly different depending on their cut.

Color Grade

Describes how colorless the diamond is (D = perfectly colorless → Z = noticeable warmth).
Lab-grown diamonds often achieve D–H grades, offering exceptional brightness.

Explore: The 4Cs of Lab-Grown Diamonds

Clarity Grade

Measures internal inclusions or surface blemishes under 10x magnification.
Common grades: IF, VVS, VS, SI.
At BÄL, we primarily offer diamonds graded VS or higher for a flawless visual experience.

Cut Grade

Reflects how well the diamond is proportioned and faceted.
Grades range from Excellent to Poor and directly influence brilliance.

💡 BÄL Tip: Always choose Excellent or Ideal cuts for optimal sparkle.

Polish & Symmetry

These indicate the precision of the cutting process and surface finish.

• Polish = smoothness of facets
• Symmetry = how evenly facets are aligned
  Both should ideally be Excellent or Very Good.
  

Fluorescence

Describes how a diamond reacts to ultraviolet light.
Grades range from None to Strong Blue.
It’s a natural effect not a flaw but “None” or “Faint” is preferred for maximum transparency.

Growth Method (Lab-Grown Reports Only)

Lab-grown certificates mention whether the diamond was grown by CVD or HPHT confirming transparency of origin.

Learn more: How Lab Diamonds Are Made (CVD vs HPHT)