I just googled ice.com and the pricescope forums and I found this: ice.com good deal? : Show Me the Bling! (Rings,Earrings,Jewelry) ? Diamond Jewelry Forum - Compare Diamond Prices, Discussions & Diamond Information
Based on the link you gave, it did not give a standard description of diamond (like what @Spoon mentioned).
Go to the tutorial at bluenile.com so you can perform due diligence on the diamond and ring setting you want.
Check out https://www.diamonds.pro
for reviews of online retailers as well.
The 3 sites I went shopping for my fiance's engagement ring are:
I believe if you're a pricescope.com forum member, you get some discounts on a few of the more reputable online diamond and ring dealers (check out pricescope for more details).
In the end, I purchased at jamesallen.com. Very helpful folks at that site and I would definitely recommend. Good luck!