IGI Certified Diamonds

Is IGI Certification the Right Choice?

The International Gemological Institute (IGI) is the largest grader of lab-grown diamonds globally and a major player in natural diamond grading, particularly in the European and Indian markets. IGI certificates are widely accepted by jewelers, banks, and insurance companies. Functionally interchangeable with GIA for most practical purposes, and significantly more common in lab-grown inventory.

Stones carrying a IGI certificate trade at about a 140.9% premium over the market baseline in our data. That's the 'GIA effect' at work. Buyers trust the grading rigour and are willing to pay for it. If you're going to resell the stone or want the most conservative paper trail, the premium is real and worth considering.

IGI certificates cover 13,805,825 listings in our database, and the overwhelming majority are lab-grown, 13,430,167 lab stones vs 375,526 natural. This is the lab-grown industry's dominant certificate: efficient, affordable, and comfortable with the volumes of lab output hitting the market.

Most of the IGI-certified inventory we track is in ROUND (4,927,658 listings). Consistent with round being the default for engagement-ring buyers. If you're shopping fancy shapes, selection thins out quickly across every lab; widening your search to two or more certificate issuers often doubles the available inventory.

For lab-grown diamonds IGI is the default choice. Cheaper, faster, and with no discount on quality of grading. For natural diamonds IGI is well-accepted in most markets but traditionally has graded slightly softer on color and clarity than GIA, which is priced into the market. A GIA certificate on a natural stone will still command a small premium on resale.