IGI Certification Explained: How to Read a Diamond Certificate Before You Buy

Every diamond we sell ships with an IGI certificate. Here is what that document actually tells you, why it matters more than any sales pitch, and how to read one before you buy.

What Is IGI?

The International Gemological Institute is one of the world's largest independent diamond grading laboratories, and the global leader in certifying lab-grown diamonds. An IGI report is an impartial assessment of your stone by gemologists who have no stake in the sale — which is precisely the point.

The 4Cs, In Plain Language

• Cut — how well the stone's proportions return light. This is the single biggest driver of sparkle, and the one C worth paying up for. Grades run from Excellent to Poor.
• Colour — graded D (colourless) to Z (visibly tinted). For most jewellery, D–F is colourless and G–H is near-colourless and excellent value.
• Clarity — the presence of internal inclusions, from FL (flawless) to I (included). VS1–VS2 stones look clean to the naked eye at a fraction of flawless pricing.
• Carat — weight, not size. Elongated shapes like oval, marquise and pear look larger per carat than rounds.

How to Verify a Certificate

Every IGI report carries a unique number. Enter it at igi.org's report-check tool and the full grading appears — independently of whatever the seller told you. If a jeweller cannot produce a certificate number that verifies online, walk away.

Why This Matters Doubly for Lab-Grown

Because lab-grown diamonds are priced well below natural stones, some sellers cut corners on grading. A certified lab-grown diamond removes the guesswork: you know exactly what you own, and the stone's identity as lab-grown is stated plainly on the report. That transparency is the foundation our engagement rings, mangalsutras and earrings are sold on.

Have a certificate you'd like help reading? Message us — or browse the full IGI-certified collection.