Clarity

Clarity refers to the purity of the diamond crystal. Diamond crystals are virtually 100% carbon and they are formed approximately 75 to 120 miles beneath the Earth's surface. Very few diamonds in engagement rings are totally flawless and most diamonds have one or more internal inclusions within their structure. Normally these only affect transparency and brilliance when the inclusions are sufficiently large enough to be seen with the unaided eye. However the less inclusions in the diamond, the more valuable it is - simply because the rarity factor comes into play. All diamonds are graded face up under 10X magnification. The GIA clarity scale of grading is as follows:

Other gem laboratories such as the EGL use the SI3 grade for "good" I1 stones.