This is a comparison of 0.90ct ideal cut, H color, SI1 clarity Round cut diamonds (click the dollar amount to be taken directly to the diamond):

James Allen: $3600

Abazias: $4184

White Flash: $4268

Blue Nile: $4277

Brilliant Earth: $4530

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. For everything you need to know about buying engagement rings online, please visit http://howiboughtthering.com.