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Tough Call

pmb773

Rough_Rock
Joined
Feb 28, 2013
Messages
3
Hi,

I'm having a hard time deciding between two diamonds and wanted to get people's opinion. Here are their specs:

Diamond 1
1.94 ct brilliant round
Triple excellent cut
SI2
H Color
Cost is $17k

Diamond 2
1.70 ct brilliant round
Triple excellent cut
SI1
G Color
Cost is also $17k

The guidance I have from my girlfriend is she likes "a big rock with a small band." She said this in a kind of jokey way but I know deep down that's what she'd like, so long as it doesn't look gaudy or ostentatious. She's 5'5" and has small to medium sized hands (my best guess is that she'd wear a size 6). I've only done the naked eye test for both stones and it's pretty hard to tell the difference with the exception of size. I'm considering going back to see the stones under a scope though wanted to see if anyone else was weighing a similar decision. Appreciate anyone's thoughts!
 
Would you be able to post the specs on the stones here? Are they GIA or AGS graded? If so, what is the cut grade (eg: EX, Ideal)

These are the numbers that will help the most so people can look at and see how well the angles on the stone will be working together:

table size
depth %
pavilion angle
crown angle
diameter

Color is a personal preference and most people are going to be fine with a GIA G or H. The quality of cut is what makes the diamond sparkley, not color or clarity (except perhaps certain kinds of inclusions). For clarity at that size, SI 1 might be a better choice, but if the SI2 is eyeclean to you and none of the particular types of inclusions will hamper light performance, there's no reason you can't consider it as well.

ETA- Oops- just saw the EX EX EX, so I'm guessing these are GIA. The particulars would still be helpful for people here, as GIA EX is a fairly broad category and so some weedout may be necessary.
 
Some more info on the two diamonds:

For the 1.94 ct Ex Ex Ex stone with color grade H and SI2 clarity:
62.6% depth
57% table size
35.5 degree crown angle
41.2 degree pavilion angle
girdle - slightly thick

For the 1.70 ct Ex Ex Ex stone with color grade G and SI1 clarity:
60.8% depth
58% table size
34.5 degree crown angle
41.2 degree pavilion angle
girdle - slightly thick

Both diamonds are priced virtually identically. Thoughts? Thanks!
 
The one thing you are missing are the diameter measurements. The first stone is too deep, so it probably won't face up as large as it could if the depth was better. The second one has a great depth, so it should face up with a nice diameter. I would 1000 times rather have a G SI1 over an H SI2, so by numbers only, I'd have to choose the 1.7 G. But I'd like to see magnified photos of the stones and idealscope images, if possible. You really need idealscopes on both, because with those pavilion angles, you may have some leakage or less bright centers. However, #2 still is better on that aspect as well.
 
OP, if you search "cheat sheet" here, you'll find several threads that discuss a set of dimension and angle ranges that are likely to help you pick diamonds just from the specs. A little leakage under the table had been deemed okay now, so some PS people object to the "cheat sheet" now because it limits you to a very small subset of all RB diamonds.

Crown and pavilion angles are a relationship with each other. Increase one and almost always have to decrease the other. You can plug the depth, table, angles into the HCA tool here. Score 2 or under is what predicts best light performance. HCA is a rejection tool, so low score like .8 is not better than 1.1, etc.

Eye-clean diamonds in the SI2 range are rare now in any size. Those get snatched up fast. SI2 will likely have visible inclusions and especially that's a risk with close to a 2ct. The larger the diamond, the more likely a SI1 or SI2 inclusion will show. And also, the more the diamond concentrates color and shows tint.
 
Without getting too technical, I'd say pick which one looks best to you. It sounds like you're getting what you pay for in either case.

Pay close attention to the SI2 to see if you notice the inclusion with your naked eye. Look until you find it. Maybe it bothers you, maybe not, but remember it might be more noticeable when the stone is dirty and out of lighting.

Triple X sounds solid but you can always take each stone out of the bright lighting, closer to daylight and play with them to find which one sparkles better. If you just can't tell, then you have your answer on cutting.

Either one is "big rock" in my book. :wink2: Good luck with your purchase!
 
IMO the size difference is not that much.
 
Thanks for all the great advice so far. On the question about the diameter, here are the measurements:

Diamond #1 (1.94 ct H) - 7.94 - 7.96 x 4.99mm
Diamond #2 (1.70 ct G) - 7.66 - 7.71 x 4.67mm

Thanks!
 
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