This is a comparison of 2ct ideal cut, D color, VS2 clarity round cut diamonds (click the dollar amount to be taken directly to the diamond):

James Allen: $30,420

White Flash: $33,191

Blue Nile: $37,073

Abazias: $39,059

Brilliant Earth: $40,270

These diamonds are independently inspected and graded by GIA/AGS, which means you can trust their quality. The quality of these diamonds is identical--the only thing that is different is the price.