The GIA Diamond clarity-scale refers to how clean, or free of imperfections a Diamond is. The GIA standard for the clarity scale consists of:

FL, IF, VVS1, VVS2, VS1, VS2, SI1, SI2, ???, I1, I2, I3

So what is the SI3?

The SI3 was born out of the desire of the Diamond Industry to incorporate an extra grade to identify Diamonds in the lower range of the clarity scale. Many complained that there is too wide a gap between the SI2 and the I1 grade. Why not offer an SI3 grade to bridge the gap?

After EGL - Los Angeles (European Gemological Laboratory) started to issue the SI3 grade, even the Rapaport Diamond Report, or the Rap Sheet as it's known in the trade, added SI3 to its price list. For those who are unfamiliar with the Rap sheet, it is the definitive (but no longer only) price guide for Diamonds. It is used widely by the wholesale as well as retail industry.

Some say the SI3 is a good idea, others say it is a bad idea. We feel that it can be a good idea if implemented properly.

The problem with the SI3 today is that GIA, the largest and most widely accepted Gem Laboratory in the world, does not recognize SI3 grades. Bill Boyajian, President of GIA, wrote the following letter to Jewelers’ Circular Keystone JCK Magazine in May 2002:

“We have studied the SI3 suggestion at various times over the years, and yet again recently when proposed and adopted in principle by the World Federation of Diamond Bourses. However, GIA still concludes there is no reason to change our long-standing and universally accepted diamond grading system.”