IF	Internally Flawless	No inclusions visible at  10x magnification
VVS1	Very Very Slightly Included #1	Inclusions that are extremely difficult to locate at 10x
VVS2	Very Very Slightly Included #2	Inclusions that are very difficult to locate at 10x
VS1	Very Slightly Included #1	Inclusions that are difficult to locate at 10x
VS2	Very Slightly Included #2	Inclusions that are quite difficult to locate at 10x

SI1	Slightly Included #1	Inclusions that are easy to locate at 10x
SI2	Slightly Included #2	Inclusions that are very easy to locate at 10x
I1	Included #1	Inclusions that may be visible to the unaided eye
I2	Included #2	Inclusions that are visible to the unaided eye
I3	Included #3	Multiple inclusions that are obvious to the unaided eye

 

The cut of a diamond is perhaps the most importamt of the 4 Cs. The brilliance of a diamond depends very much on the amount of light that is reflected to the eye, and the quality of the cut is all-important in this respect. There are many factors which determine the quality of a diamond's cut, but the two most important are the depth percentage and the table percentage. Crown angle and crown height are also very important. For an excellent illustration of the factors affecting diamond cut, visit the following web page and click "Education and Guidance" in the right hand column: Search for Diamonds at Blue Nile

 

 

The Four Cs
Before you start diamond shopping, you want to have an understanding of what you're buying. This guide simplifies the four C's of a diamond's cut, colour, clarity, and carat weight, so you can select your diamond based on the same criteria jewellers use to grade them. After reading through this guide, you'll be ready to choose the diamond that's right for you.

Cut
The cut of a diamond has the most effect on its sparkle, or brilliance. Even if the diamond has perfect colour and clarity, a poor cut can make a diamond look dull. Blue Nile carries only the highest grades of diamond cut, for the most sparkle.

Colour
Diamonds with very little colour are the most highly valued and priced accordingly. A little color can diminish a diamond's brilliance. To help you choose the most brilliant diamond, Blue Nile offers diamonds with the highest grades of color.

Clarity
Diamonds with few flaws, or inclusions, are very rare and highly valued. Clarity is graded based on the number, location, size and type of the inclusions found in a diamond. Blue Nile has some of the clearest diamonds available.

Carat Weight
The weight of a diamond is measured in carats. Since larger diamonds are more rare than smaller diamonds, diamond value tends to rise exponentially with carat weight.