How to Read an IGI Diamond Certificate
Your diamond's IGI certificate decodes its quality. Learn what every line means — cut, colour, clarity, carat, and how to verify it's genuine.
Every Luzora diamond arrives with an IGI certificate — your independent proof of exactly what you own. But a grading report can look like a wall of jargon. Here's how to read it, line by line.
What is IGI?
The International Gemological Institute is one of the world's leading independent diamond grading laboratories. "Independent" is the key word: IGI doesn't sell diamonds, so its grading is unbiased. A certificate is essentially a diamond's identity document, confirming its 4Cs and confirming it is lab grown.
The 4Cs on your certificate
Carat weight — the diamond's weight, listed to two decimal places (e.g. 1.00 ct). Remember: this is weight, not physical size.
Cut grade — how well the diamond is proportioned and finished, usually from Excellent down to Poor. This drives sparkle, so it's the grade worth prioritising.
Colour grade — on the D-to-Z scale, where D is completely colourless. Luzora diamonds are always G or better, meaning they read as white to the eye.
Clarity grade — from Flawless (FL) down through VVS, VS, SI, to Included (I). Luzora diamonds are always VS or better, which means eye-clean.
The other details
Shape and cutting style — round brilliant, oval, emerald cut, and so on.
Measurements — the diamond's dimensions in millimetres (length × width × depth).
Polish and symmetry — how well the facets are finished and aligned. Look for Excellent or Very Good.
Fluorescence — whether the diamond glows under UV light. Usually "None" or "Faint," and rarely something to worry about.
"Laboratory Grown" statement — an IGI report for a lab grown diamond states this clearly, along with the growth method where noted.
The laser inscription
Many certified diamonds carry a microscopic laser inscription on the girdle — a unique report number matching the certificate. It's invisible to the naked eye but confirms the stone and paper belong together.
How to verify it's genuine
Every IGI report has a report number. You can enter that number into IGI's official online report-check tool to confirm the certificate matches their records. If the details on screen match your paper, you're holding the real thing.
Certified, every time
We never ask you to take quality on trust. Every Luzora diamond is IGI certified — G colour or better, VS clarity or better — grown and cut in-house.
