Igi Vs Gia Diamond Grading

Igi stands for international gemological institute.

Igi vs gia diamond grading. The gemological science international gsi is an adequate lab that will at times have one or two grade inconsistencies. To be very clear an ideal rating from igi doesn t mean that the diamond is better cut than an excellent rating from gia. Unfortunately the european gemological laboratory egl has lost much of its credibility and market share. Like the egl this for profit diamond certification lab is prominent throughout europe but is also popular in the united states.

This shows that the gia employs much stricter standards than the igi. The international gemological institute igi is also improving its process of grading diamonds. Igi was looser in 7 cases e g. Igi vs gia color grading the igi and the gia do not use similar color grading techniques.

Typically clarity and color grades of egl igi diamonds are off by at least 2 4 ratings if the same diamond was to be graded by gia or ags instead. Gia color grading summary results of the color grade comparison are shown in table 2. For example a diamond graded to be g color by egl igi might probably be graded as an i color by gia ags. Igi graded a diamond g color while gia graded it h color.

Igi was stricter than gia in 12 cases e g. Taking the average of the differences of all of these specific color clarity combinations weighing each coordinate on the matrix equally leads to the conclusion that gia certified diamonds are 18 77 more expensive than igi certified diamonds on average at least for 1 00 1 49ct diamonds. However if you are considering an igi graded diamond read our tips below carefully so you know exactly what you are in for in order to make an informed decision while buying loose diamondsas well as to avoid making certain mistakes. Igi simply uses different nomenclature for their cut grading and this does not mean that igi is better than gia in that regard.

In a nutshell igi is not as consistent or strict in grading diamonds as gia. The same goes for diamond clarity grading. For example a j color diamond from igi will look darker and have a bit more tint than a j color diamond graded by the gia.