Spread - Cushion vs. RB

[shannonv]

I am clueless...Any suggestions as to what a good spread would be for a 1.2 carat cushion cut? I know for a RB it is around 6.5mm for 1 carat, 7 for 1.25. Is it similar for a cushion? I know that RB look bigger than their cushion counterparts of the same weight. What spread would make a 1.2 cushion cut look similar in size to a 1.2 RB? I know there are a lot of factors, but I am just looking for a range.

Any suggestions?

 

[lmurden]

http://www.bluenile.com/diamonds_details.asp?pid=LD00342096&item=8_11&filter_id=0&sec=&query=&page=1&sortby=ranking

1.20carats
6.96x5.97x3.98 mm

http://www.bluenile.com/diamonds_details.asp?pid=LD00400833&item=0_11&filter_id=0&sec=&query=&page=1&sortby=ranking

1.25 carats
6.96x6.15x3.67 mm