Same Carat, Similar Cut, different sizes?

[godzillinois]

So I've been looking on Blue Nile for weeks now, comparing different combinations etc. I found a diamond that's an Ideal Cut, I color, eye clean SI2 at 0.66 ct. It's measurements are 5.58 x 5.59 x 3.47 mm. Now I saw one in a brick and mortar store that was also 0.66 ct, G/H color SI2. It's EGL certified and they didn't have the cut quality, but it's measurements were 5.37 x 5.35 x 3.5 mm. These were both round diamonds, how could the measurements be that different? I also noticed that most of the stones in the physical store were all smaller mm-wise compared to their Blue Nile carat counterparts. Is EGL and GIA that different from each other?

Also, I'm wondering if you guys think the Blue Nile diamond will be comparable (or better) looking to the EGL certified one I saw today? I know that one is an I color and the one I saw was G/H, but I'm assuming its at least a slightly better cut and measurement-wise it is about 0.20 mm bigger. I mean, Ideal cut is pretty much the best GIA cut right?

I was looking at a bunch of J color ones (at a Blue Nile representative's suggestion) but all the J's I saw in person today showed too much color to me. The two I color ones I saw in person today had only a slightly noticeable difference to the E, F, G and Hs I saw which is why I'm settling for an I color. Now the Blue Nile ring will be around $300-$400 cheaper than the EGL ring I saw today, but if I change the color in the Blue Nile diamond to an H it actually costs the same minus tax to the diamond I saw for sale today. Then again, there's that 0.20mm difference still. What do you guys think? Your help is greatly appreciated, I'm looking to buy something either today or tomorrow. Thanks in advance!

 

[JulieN]

probably cut deep, and/or thick girdle. 5.36 is much too small.

5.6 mm is about right for a .66

 

[godzillinois]

So it seems that GIA certification is more strict than EGL? In that case do you guys think a GIA "I color" will be as white or better than an EGL "G/H color?" I can also get the same exact ring on Blue Nile in an "H color" for $170 more, would that be worth the one step up in color?

Or I can get a 0.60 ct Ideal-cut, I-color and VS2-clarity at 5.51 x 5.48 x 3.27 mm with a strong Fluorescence? Both are pretty much the same exact price.

 

[JulieN]

GIA has a cut grade that penalizes for a thick girdle, it is one thing that can drop the cut grade to Very Good. EGL doesn't have a cut grade, to my knowledge.

 

[godzillinois]

I see, then I should probably just go with GIA all the way. What do you guys think of these Blue Nile options:

0.66 ct: Ideal Cut, I color, eye clean SI2 at 5.58 x 5.59 x 3.47 mm

0.60 ct: Ideal-cut, I-color and VS2-clarity at 5.51 x 5.48 x 3.27 mm with a strong Fluorescence

or upgrade the first option for $170 more to a H COLOR 0.66 ct: Ideal Cut, SI2 at 5.58 x 5.60 x 3.43 mm? (weirdly this one is AGS certified as opposed to GIA on Blue Nile's site.)


Or should I just post this question as a seperate/new thread?

 

[tyty333]

You need to put them on hold and give us links so we can look at the angles to let you know
which stone would be your beet bet. Did you find out if the SI2 stone is eye clean?

Edit - if you let us know your budget we can point out well cut stones.

 

[godzillinois]

http://imgur.com/49YmMN4.jpg

http://i.imgur.com/smGrr1E.jpg

My budget is around $1700

 

[distracts]

The Blue Nile one will have better light performance. If you were happy with the EGL I colors, you may be happy with GIA J or even K, however if the I is within your budget I'd just go for it. With a 2/3 carat size diamond, I wouldn't up the clarity to VS2. Maybe Si1 if you really want, but if I was doing anything there I'd make it a little bigger, see if you could hit .75 cts. But I think the Blue Nile one you like now is a good size and good balance of color/clarity.

 

[godzillinois]

The Blue Nile one will have better light performance. If you were happy with the EGL I colors, you may be happy with GIA J or even K, however if the I is within your budget I'd just go for it. With a 2/3 carat size diamond, I wouldn't up the clarity to VS2. Maybe Si1 if you really want, but if I was doing anything there I'd make it a little bigger, see if you could hit .75 cts. But I think the Blue Nile one you like now is a good size and good balance of color/clarity.

Thanks! I went with the 0.66 ct, after hearing about HCA from the board I found out it scored a 1.6 while the 0.60 ct scored a 3.6! Thanks again for your advice! I figured GIA color would be better but I went with an "I" anyways to be safe, plus I saw some I1s and I3s (non-GIA) in stores that were 'passable' so an eye-clean GIA SI2 will hopefully be MUCH better! Now the hard part, figuring out how to propose!