Cut

D'Selection suggests that perhaps the most important of the three Cs is Cut, so it is important to understand how this quality affects the properties and value of a diamond. 

An excellent cut gives a diamond its brilliance, which is that brightness that seems to come from the very heart of a diamond. The angles and finish of any diamond are what determine its ability to handle light, which leads to brilliance.     

Excellent (EX)   Very Good (VG)   Good (G)  Fair & Poor

Clarity

When we mention a diamond's clarity we are referring to the presence of identifying characteristics within the stone. Diamonds are graded for clarity under 10x loupe magnification.  

IF - Internally Flawless: no internal flaws, but some surface flaws. Very rare.
VVS - Very Very Slightly Included (two grades). Minute inclusions very difficult to detect.
VS - Very Slightly Included (two grades). Minute inclusions seen only with difficulty under 10x magnification.
SI - Slightly Included (two grades). Minute inclusions more easily detected under 10x magnification.

Colour

A colourless diamond allows more light to pass through it than a colored diamond, therefore the colorless diamonds emit more sparkle and fire. The formation process of a diamond ensures that only a few, rare diamonds are truly colorless. Thus the whiter a diamond color, the greater its value.