shape
carat
color
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RB Selection Assistance

bgold2j

Rough_Rock
Joined
Jan 17, 2013
Messages
5
Hi All,

Just want to say that this forum is awesome and filled with some truly dedicated and intelligent individuals. I've learned a ton in the last few weeks on here and hope I've put it to good use narrowing down my choices. If I may, I'd like to ask for your help in selecting "the one".

These are all eye-clean Round Brilliants. If I've neglected to provide any information, please let me know and I will get it asap.

Here we go:

Choice A:
weight: 1.51 cts.
Measurements: 7.34 - 7.36 x 4.53 mm
color: I
clarity: SI1
Table%: 57
Depth%: 62
Crown angle: 35.5
Pavilion angle: 40.6
Crown%: 15.4
Pavilion% 42.7
Girdle thickness: 1.4% to 4%
Cut: Excellent
Polish: Very Good
Symmetry: Excellent



Choice B:
weight: 1.50 cts.
Measurements: 7.36 - 7.40 x 4.54 mm
color: I
clarity: VS2
Table%: 54
Depth%: 61.5
Crown angle: 32.5
Pavilion angle: 41.0
Crown%: 14.5
Pavilion% 43.5
Girdle thickness: med-slightly thick (faceted) 3.5%
Cut: Excellent
Symmetry: Excellent
Polish: Very Good



Choice C:
weight: 1.50 cts.
Measurements: 7.42 - 7.46 x 4.45 mm
color: I
clarity: SI1
Table%: 59
Depth%: 59.9
Crown angle: 34.0
Pavilion angle: 40.8
Crown%: 13.5
Pavilion% 43.0
Girdle thickness: thin - slightly thick (faceted)
Polish: Very Good
Symmetry: Excellent



I'm really looking forward to the responses. Thank you all so much for your help.

idealscope-a.jpg

idealscope-b.jpg

idealscope-c.jpg
 
Love diamond B! It's gorgeous - I love the arrows on it and it scored a .8 on the HCA! Diamond A scored a 1.4 on the HCA which is also good and stone C scored a 1.3 on the HCA. I still prefer diamond B because that idealscope is gorgeous!
 
A for me. Personal preference for steeper crown... would prefer an even smaller table but can't have everything ::) still has the greatest crown height of your options, interestingly. Better odds of seeing more coloured light through a variety of lighting types and I like colour.
B is a big stone and girdle is med on the lower end so that's good, mitigates chipping concerns... lots of big bold white flashes, big bold flashes of colour in spotlights, obviously not a good choice for someone who is nitpicky about optical symmetry. C is a nice example of a different type of proportions - objectively no less beautiful, just not my personal preference. But is it clean to your specifications, whatever they are? Tell JA what YOU mean by eyeclean and have them vet the stones to your requirements - may be different from their general definition of the term 'eye-clean'.
Age of reports? Any comments in the "Additional Comments" section?
 
Thanks very much for the analysis. In terms of clarity, if I can only see the inclusion by staring at it a few inches away, and if it doesn't effect the brilliance of the diamond, I'm fine with it. My goal is to get a diamond that performs best on the fire/dispersion metric and will look great in "regular lighting"-- meaning outdoors, office lighting, etc. It's rare that I see a diamond underperform under point sources.

The reports are all from mid to late 2012. Additional comments state clouds, pinpoints, surface graining not shown on 2. One thing that's strange is there is a white "bar" that overlaps some of the comments one the third. I can only see "isps and surface graining not shown". Is it against any rules to post the certs here? Would it be helpful?
 
The first one!

It is "twinning wisps."
 
In order of preference:

Diamond A
Diamond C
Diamond B
 
If onlythe first one had a 55 table! :love: It's my choice too!
 
Another vote for A and another wish for a smaller table....what did the gemologist say about performance on them all?
 
It's probably safe to take B out of the running... which is good because that was the gemologist's least favorite.

I'm torn between A and C. The gemologist likes C the best with A being a very close second. I see lots of votes for A here and I'm leaning towards that way myself. The 59 degree crown angle on C concerns me, but then again the 35.5 crown angle on A has me a bit concerned as well. Choice A is AGS and C is GIA.... if that makes a difference.

Verdict?
 
bgold2j|1358478775|3358389 said:
It's probably safe to take B out of the running... which is good because that was the gemologist's least favorite.

I'm torn between A and C. The gemologist likes C the best with A being a very close second. I see lots of votes for A here and I'm leaning towards that way myself. The 59 degree crown angle on C concerns me, but then again the 35.5 crown angle on A has me a bit concerned as well. Choice A is AGS and C is GIA.... if that makes a difference.

Verdict?

Did they give any reasons for liking C better? Did yo uask what was brightest or what performs the best? I am just curious because the last few times this past week it just seems to me the gemologists choice leans towards a 60/60 rather than one closer to ideal proportions and I wonder why that is???

Please someone correct me if I am wrong but it just seems like the proportions on C would lean towards white light and not fire. ???
 
bastetcat|1358484027|3358457 said:
bgold2j|1358478775|3358389 said:
It's probably safe to take B out of the running... which is good because that was the gemologist's least favorite.

I'm torn between A and C. The gemologist likes C the best with A being a very close second. I see lots of votes for A here and I'm leaning towards that way myself. The 59 degree crown angle on C concerns me, but then again the 35.5 crown angle on A has me a bit concerned as well. Choice A is AGS and C is GIA.... if that makes a difference.

Verdict?

Did they give any reasons for liking C better? Did yo uask what was brightest or what performs the best? I am just curious because the last few times this past week it just seems to me the gemologists choice leans towards a 60/60 rather than one closer to ideal proportions and I wonder why that is???

Please someone correct me if I am wrong but it just seems like the proportions on C would lean towards white light and not fire. ???


I agree that stone A will likely exhibit more colored light. It's not quite FIC but I think that it will have a much better display of white and colored light than option C. I think that C is probably a very pretty and bright stone, but I prefer steep crowns and tiny tables. My RB is 55/36/40.5 and I think it's the most beautiful amazing thing I've ever seen in low lighting, and holds its on against a more TIC type stone in other lighting conditions. For me the only benefit of a 60/60 type is they tend to face up larger and be bright.

I second bastetcat about asking the gemologist why they preferred one over the other.
 
I *think* (based solely on a lot of the JA gemologist comments we've seen on here) that many of JA's gemologists prefer a brighter look - in contrast to what some of us prefer on here. Garry and David have talked about those preferences being age-related as well... OP, it really is just personal preference! (How many times can you say prefer in one paragraph?) If the table on A were smaller the crown facets would be bigger and individual dispersion wavelengths visible w/ smaller tilt, which is why some of us have been adding that blurb.

Christina feel free to send your RB my way if you ever tire of it - you know I'll take that sort of VG over any other type any day :bigsmile:
 
The gemologist's comments, relayed through a third party, were that both stones have great fire, brilliance, and scintillation, but C has slightly better light performance than A. Thanks for clarifying the reasoning behind preferring a smaller table. Are there any specific questions I should ask the gemologist? I just figured they were going off the idealscope and visual inspection and that these things come down to a certain amount of subjective opinion and might vary from gemologist to gemologist.

I also, for some reason rounded the table size when I wrote down the measurements of choice A. It's 56.7 as opposed to 57. Does that make much of a difference?
 
bgold2j|1358519724|3358638 said:
The gemologist's comments, relayed through a third party, were that both stones have great fire, brilliance, and scintillation, but C has slightly better light performance than A. Thanks for clarifying the reasoning behind preferring a smaller table. Are there any specific questions I should ask the gemologist? I just figured they were going off the idealscope and visual inspection and that these things come down to a certain amount of subjective opinion and might vary from gemologist to gemologist.

I also, for some reason rounded the table size when I wrote down the measurements of choice A. It's 56.7 as opposed to 57. Does that make much of a difference?

Yes, it takes diamond A from a 1.4 on the HCA to a 1.3 which is even better.
 
04diamond<3|1358520156|3358645 said:
bgold2j|1358519724|3358638 said:
The gemologist's comments, relayed through a third party, were that both stones have great fire, brilliance, and scintillation, but C has slightly better light performance than A. Thanks for clarifying the reasoning behind preferring a smaller table. Are there any specific questions I should ask the gemologist? I just figured they were going off the idealscope and visual inspection and that these things come down to a certain amount of subjective opinion and might vary from gemologist to gemologist.

I also, for some reason rounded the table size when I wrote down the measurements of choice A. It's 56.7 as opposed to 57. Does that make much of a difference?

Yes, it takes diamond A from a 1.4 on the HCA to a 1.3 which is even better.

No, those scores are equal -- anything 2 or below on the HCA is equally good. It is not a ranking tool. So a 1.3 on the HCA is not "better" than a 1.4. If I remember correctly, there have been threads on about HCA scores lower than 1, with some posters in those threads asserting that some diamonds that score lower than 1 *may* show obstruction.
 
bgold2j|1358519724|3358638 said:
The gemologist's comments, relayed through a third party, were that both stones have great fire, brilliance, and scintillation, but C has slightly better light performance than A. Thanks for clarifying the reasoning behind preferring a smaller table. Are there any specific questions I should ask the gemologist?
You've confirmed that they're all clean to your specifications? No flags on any of the additional info you gave us about the reports.
I just figured they were going off the idealscope and visual inspection and that these things come down to a certain amount of subjective opinion and might vary from gemologist to gemologist.
I think that's a definite possibility, they don't have your eyes and your preferences after all.

I also, for some reason rounded the table size when I wrote down the measurements of choice A. It's 56.7 as opposed to 57. Does that make much of a difference?
No. We're nitpicking. The choices you have are just fine and will all be beautiful stones, now it's down to the sorts of nuances that you might not even notice IRL...

Those are the diplomatic answers.
The not-so-diplomatic answer: I go to JA to take advantage of their prices, and I go in knowing the sort of stone I want. That's because I trust JA reps to tell me if there's something *wrong* with a stone but I'm not as confident in their evaluations of stones based on my preferences as I would be w/ WF/BGD/GOG... but of course, I'm willing to pay these vendors more for those thorough and personalised services. If you were my friend I'd tell you to choose A.
 
Thanks Yssie for the honesty. I'm a fan of non-diplomatic answers :).

Just to throw it out there, would something like the following be more preferable then A or C?

Table: 56%
Depth: 62.3%
Crown angle: 34.5
Pavilion angle: 41.0
Pavilion %: 15.0
Crown %: 43.5
Dimensions: 7.49 - 7.51 x 4.68 mm

Interestingly enough, the price is similar to the others and it's quite heavier at 1.62c. Downside is that it's a BN SI1 which I think means it might be tricky to verify that it's eye clean.
 
Yssie|1358521051|3358659 said:
bgold2j|1358519724|3358638 said:
The gemologist's comments, relayed through a third party, were that both stones have great fire, brilliance, and scintillation, but C has slightly better light performance than A. Thanks for clarifying the reasoning behind preferring a smaller table. Are there any specific questions I should ask the gemologist?
You've confirmed that they're all clean to your specifications? No flags on any of the additional info you gave us about the reports.
I just figured they were going off the idealscope and visual inspection and that these things come down to a certain amount of subjective opinion and might vary from gemologist to gemologist.
I think that's a definite possibility, they don't have your eyes and your preferences after all.

I also, for some reason rounded the table size when I wrote down the measurements of choice A. It's 56.7 as opposed to 57. Does that make much of a difference?
No. We're nitpicking. The choices you have are just fine and will all be beautiful stones, now it's down to the sorts of nuances that you might not even notice IRL...

Those are the diplomatic answers.
The not-so-diplomatic answer: I go to JA to take advantage of their prices, and I go in knowing the sort of stone I want. That's because I trust JA reps to tell me if there's something *wrong* with a stone but I'm not as confident in their evaluations of stones based on my preferences as I would be w/ WF/BGD/GOG... but of course, I'm willing to pay these vendors more for those thorough and personalised services. If you were my friend I'd tell you to choose A.

I'd agree with Yssie on everything she's just said.

And Christina and Yssie- thank you for explaining that. It certainly helps me understand some of the things I have seen.

OP- I'd bet the change in table size you posted makes only a minute difference to the optics, possibly not enough to see with our own eyes.
 
bgold2j|1358521466|3358665 said:
Thanks Yssie for the honesty. I'm a fan of non-diplomatic answers :).

Just to throw it out there, would something like the following be more preferable then A or C?

Table: 56%
Depth: 62.3%
Crown angle: 34.5
Pavilion angle: 41.0
Pavilion %: 15.0
Crown %: 43.5
Dimensions: 7.49 - 7.51 x 4.68 mm

Interestingly enough, the price is similar to the others and it's quite heavier at 1.62c. Downside is that it's a BN SI1 which I think means it might be tricky to verify that it's eye clean.

I ran the HCA on it and got 1.9 w/ EX Vg Vg Vg on the results. Maybe it's the bit of extra depth and pavilion angle combined?
 
bgold2j|1358521466|3358665 said:
Thanks Yssie for the honesty. I'm a fan of non-diplomatic answers :).

Just to throw it out there, would something like the following be more preferable then A or C?

Table: 56%
Depth: 62.3%
Crown angle: 34.5
Pavilion angle: 41.0
Pavilion %: 15.0
Crown %: 43.5
Dimensions: 7.49 - 7.51 x 4.68 mm

Interestingly enough, the price is similar to the others and it's quite heavier at 1.62c. Downside is that it's a BN SI1 which I think means it might be tricky to verify that it's eye clean.


GIA, right?
Age of report?
Girdle/LGF/star?
Any comments in the Additional Comments section or noted on the proportions diagram?
Fluor?
Is it a BN Signature? Those are in-house.

It's heavier but won't face-up notably larger - that 0.1-0.15mm increase in diameter is trivial.

BN doesn't provide any pictures or scans of their non-signature stones (at least w/ the Signature line you get the GCAL as well...). GIA averages measurements around the eight sections of stone, rounds those averages, and prints the outputs on the report - we don't know anything about variations around the stone or variance in averaging/rounding, and we know nothing about optical symmetry (symmetry noted on the report is "physical"/"facet-meet" symmetry, they're related but optical symmetry doesn't directly depend on and can't be determined by sym noted on the report)... so all in all you have a LOT more info on the JA, and knowing what you're buying is IMO the most important thing.

Assuming the BN is lovely with those proportions, excellent optical symmetry, etc. my pick is still A from JA - but now we really are down to nitpicking of both the diplomatic and not-diplomatic sorts! ::)
 
bastetcat|1358521979|3358670 said:
bgold2j|1358521466|3358665 said:
Thanks Yssie for the honesty. I'm a fan of non-diplomatic answers :).

Just to throw it out there, would something like the following be more preferable then A or C?

Table: 56%
Depth: 62.3%
Crown angle: 34.5
Pavilion angle: 41.0
Pavilion %: 15.0
Crown %: 43.5
Dimensions: 7.49 - 7.51 x 4.68 mm

Interestingly enough, the price is similar to the others and it's quite heavier at 1.62c. Downside is that it's a BN SI1 which I think means it might be tricky to verify that it's eye clean.

I ran the HCA on it and got 1.9 w/ EX Vg Vg Vg on the results. Maybe it's the bit of extra depth and pavilion angle combined?

Yes, that crown angle is a bit steep for a 41 pavilion angle. However, the HCA score is 1.9, which is 2 or below, so it's worth considering. If these numbers come from a GIA report, it's important to remember that GIA rounds its numbers, so there's some built in guesswork whenever one tries to extrapolate how the diamond will look in person from just the numbers.
 
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