When buying a diamond, consider the "4 Cs" to judge its quality & cost: color, clarity, cut & this weight
However, if the diamond 
has color below Z it is considered fancy color and then the prices will start to go 
back up... [DOC] [TLE] How To Choose A Diamond | Diamond Buying Step by Step [PAR] Diamond buying tips for making the best compromises between Cut, Color, 
Clarity, ...