How to Read an IGI Diamond Certificate: A Simple Guide

Two diamonds can look almost the same in a photo and still be very different in quality and price. That is why a diamond certificate, also called a grading report, is one of the most important things to check before you buy.

At Saiji Diamond, our natural diamonds are certified by IGI (International Gemological Institute), one of the world's largest independent gem labs, with laboratories in India including Mumbai. In this guide we walk you through an IGI report step by step.

Why a diamond certificate matters

A certificate is an independent lab's assessment of your diamond. The jeweller does not grade the stone; the lab does. This protects you in three ways:

• It confirms the diamond is natural or laboratory-grown.
• It records the diamond's quality grades, so you can compare prices fairly.
• It gives you a report number you can verify online and use for insurance or future resale.

Two types of IGI reports you may see

1. Diamond (solitaire) report

This report covers a single loose or mounted diamond, usually a solitaire. It lists exact measurements and individual grades.

2. Jewellery report

Many diamond pieces, such as cluster rings and nose pins, contain several small diamonds. Instead of grading each tiny stone separately, IGI issues a jewellery report describing the piece as a whole: the total diamond weight, the number of diamonds, and a colour and clarity range such as E-F colour, VVS clarity.

What each section of an IGI report means

Report number

A unique number printed on the report and often laser-inscribed on the diamond's girdle (its outer edge) for solitaires. Use it to verify the report on IGI's official website.

Description

States what the item is, for example natural diamond or laboratory-grown diamond, and for jewellery reports, the type of piece and metal.

Shape and cutting style

The outline of the diamond, such as round brilliant, marquise, pear or oval.

Carat weight

The weight of the diamond. One carat equals 0.2 grams. For jewellery reports this is the total diamond weight of all stones combined.

Colour grade

Graded on a scale from D (colourless) down to Z (noticeable yellow tint). D, E and F are in the colourless range and are the most prized. G to J are near-colourless and still look white to most eyes.

Clarity grade

Measures tiny internal features (inclusions) and surface marks (blemishes), as seen under 10x magnification:

• FL / IF: Flawless or internally flawless
• VVS1 / VVS2: Very, very slightly included. Inclusions are extremely hard to find even under magnification.
• VS1 / VS2: Very slightly included
• SI1 / SI2: Slightly included
• I1 to I3: Included, sometimes visible to the eye

Cut, polish and symmetry

For round diamonds, the cut grade (for example Ideal or Excellent) tells you how well the diamond reflects light. Polish and symmetry describe the finishing quality. Better cut means more sparkle.

Fluorescence

Describes whether the diamond glows under UV light. Most fluorescence has no visible effect in normal lighting.

Plotting diagram

On full solitaire reports, a map showing where the inclusions are located, like a fingerprint of your diamond.

What does “VVS, EF” mean on our jewellery?

Many Saiji Diamond pieces use natural diamonds graded E-F colour and VVS clarity. In plain words: the diamonds are in the colourless range and have extremely few inclusions, so they look bright, white and clean. This is a high quality level for everyday diamond jewellery.

How to verify an IGI report online

1. Go to IGI's official website and open the report verification page.
2. Enter the report number printed on your certificate.
3. Check that the details online match your paper report: shape, weight, colour, clarity and whether the diamond is natural.

If anything does not match, ask the seller before you pay.

Shop certified diamond jewellery

Every Saiji Diamond piece is made with IGI-certified natural diamonds and BIS hallmarked gold, direct from our Mumbai manufacturing unit. Explore our diamond rings, engagement rings and diamond nose pins.

Frequently asked questions

Is IGI a good certification?

Yes. IGI is one of the most widely used independent gem labs in the world and is very common for certified diamond jewellery in India.

Is VVS clarity good?

Yes. VVS diamonds have inclusions so small they are very hard to see even under 10x magnification. To the naked eye they look completely clean.

Should I buy diamond jewellery without a certificate?

We do not recommend it. Without an independent report you cannot be sure whether a diamond is natural or what quality you are paying for.

Will I receive the IGI certificate with my order?

Yes, certification comes with your purchase. If you have questions about a specific piece, contact us.