Diamond Education

This short tutorial explains the 4Cs of Diamonds - cut, colour, clarity, and carat weight - the most important characteristics to understand when making a diamond purchase.

Cut

The most important of the 4Cs is cut because it has the greatest influence on a diamond's sparkle.

Learn More About Cut

Colour

The second most important of the 4Cs is colour, which refers to a diamond's lack of colour. The less colour, the higher the grade.

Learn More About Colour

Clarity

Often the least important of the 4Cs because the tiny imperfections are often microscopic.

Learn More About Clarity

Carat

The term carat actually refers to the diamond's total weight and not its size.

Learn More About Carat

Shape

Each diamond shape has different attributes that affect price and quality grade.

Learn More About Shape

Certification

Unbiased diamond grading reports are offered with every Blue Nile diamond.

Learn More About Certification

As the largest online diamond retailer, Blue Nile offers the largest collection of the world's finest cut diamonds. Pre-selected for exceptional quality, the cut, colour, and clarity of our loose diamonds are evaluated based on a standardized grading scale. Also, each loose diamond is accompanied by a grading report from either GIA, AGSL, or GemEx, independent diamond grading labs with stringent grading and certification guidelines.