Question for RHINO - What are the percentage of stones that scores...

[Dancing Fire]

triple very high on the Bscope? Does all of these triple very high score always do well with the ISEE2 machine and vice versa?

 

[valeria101]

Not excatly whom you asked, but the issue got some discussion and feedback already - if you find time to search 'Rhono's' posts for "Isee2".


On one thread in particluar (about which instument is preferable for ranking briliance) ISee2 was mentioned as the most demanding test. The Bscope does not take into account symetry (only via it's impact on brilliance) while Isee2 does - so a stone with so-so symmetry but great light return would get 'degraded' by Isee2. The 'imperfect' H&A would make good examples in this category.

Otherwise, the b-scores are highly correlated (not to say about the same) with the corresponding Isee scores: at least among the couple dozen stones in Jonathan's "educational diamonds" collection.

Jonathan's picks usually get Isee scores above 9 - a pretty lofty neighbourhood already. Max is 9.8... Non-H&As would get 5-6 'cause of symmetry alone.

Hope this helps....

 

[Magnum]

The brilliancescope measures a stone's performance in direct light conditions, while the ISEE2 measures a stone's performance in diffuse light conditions. While exceptionally cut stones will tend to do extremely well on both machines, it is not a hard and fast rule. I think Rhino has said there's a little better chance that a stone that does extrememly well on the ISEE2 will do extremely well on the BS, than a stone that does extremely well on the BS doing extremely well on the ISEE2, partially due to the symmetry that the ISEE2 measures, which is I think why Rhino has said that if he had to pick between the two machines, he would slightly favor the ISEE2 machine.. To answer your question more simply, no, a stone that scores VH/VH/VH on the brilliancescope will not always score extremely high on the ISEE2 and vice versa. A lot of times, but not always.

 

[Rhino]

Let's tackle this 2 part question one at a time.

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On 5/1/2004 3:23:12 PM vtigger86 wrote:











1. What are the percentage of stones that scores triple very high on the Bscope

If you mean to ask what percentage of *all* stones truly score tripe very high on the Brilliancescope ... consider this. It is reported that less than 1% of all diamonds cut on the market meet the standards for what strict, conservative graders would consider true Hearts & Arrows diamonds. Among that small niche of true H&A's an even smaller percentage of those score triple very highs on the BrillianceScope. Among 99.9% of the factories that cut true H&A's a very very small percentage of those actually get triple very highs on the BrillianceScope. The practical benefits of BrillianceScope testing reflects how the diamond will appear in direct or strong light conditions. The question has been raised as to what the BrillianceScope is actually measuring. A safe and simple answer to that question is "total overall brilliance in direct light conditions". People come to our store every day to draw these comparisons with their own 2 eyes. Today we had the opportunity of helping a gentleman for whom we called in 3 Lucere diamonds. Before I even showed him the BrillianceScope results on any of them I let him see all of them with his own 2 eyes in the appropriate light conditions and he, very easily picked out the most superior stone. It was no surprise that *that* particular stone was the one with the best BrillianceScope results.

2. Does all of these triple very high score always do well with the ISEE2 machine and vice versa?

Absolutely NOT. As magnum properly pointed out this is a completely different optical analysis. I have had the opportunity to test and analyze many diamonds (H&A & non) that do outstanding on the Brillancescope and not so good on the Isee2 and vice versa. Some of this is discussed and demonstrated in our tutorial on the subject. It is the rarest of H&A cuts that get the highest results on both technologies. A characteristic that will be part of what will constitute our signature line once we get that rolling.

Hope that helps.

 

[valeria101]

Sorry I jumped in, I should have waited

especially since the dsired answer seems to contain a scare: - the mention of H&A stones with less than great brilliance!



Taking it by points:

#1 (true or false) the H&A pattern promisses both superior symmetry and the right proportions for good light return (since those harts and arrows are formed by reflections inside the stone, the same factor that determines the components of light return).

#2 (true or false) some dude of a diamond can have great symmetry - all you need are the wrong proportions cut with great precision.

------------------------------------

So... Can the H&A pattern still be formed 'correctly' with prportions not consistent with the requirement for good brilliance ( as I try to grasp this, in those stones with better total Isee2 score 'cause of symmetry and low Bscope ' cause of wrong proportions ).


[if this is downright stupid, I'm redy to give up

, at last
with the required appologies and commitment to take back and delete all
simmilar ranting ]

 

[Dancing Fire]

----------------
On 5/1/2004 11:46:12 PM Rhino wrote:

Let's tackle this 2 part question one at a time.

----------------
On 5/1/2004 3:23:12 PM vtigger86 wrote:






1. What are the percentage of stones that scores triple very high on the Bscope

If you mean to ask what percentage of *all* stones truly score tripe very high on the Brilliancescope ... consider this. It is reported that less than 1% of all diamonds cut on the market meet the standards for what strict, conservative graders would consider true Hearts & Arrows diamonds. Among that small niche of true H&A's an even smaller percentage of those score triple very highs on the BrillianceScope. Among 99.9% of the factories that cut true H&A's a very very small percentage of those actually get triple very highs on the BrillianceScope. The practical benefits of BrillianceScope testing reflects how the diamond will appear in direct or strong light conditions. The question has been raised as to what the BrillianceScope is actually measuring. A safe and simple answer to that question is 'total overall brilliance in direct light conditions'. People come to our store every day to draw these comparisons with their own 2 eyes. Today we had the opportunity of helping a gentleman for whom we called in 3 Lucere diamonds. Before I even showed him the BrillianceScope results on any of them I let him see all of them with his own 2 eyes in the appropriate light conditions and he, very easily picked out the most superior stone. It was no surprise that *that* particular stone was the one with the best BrillianceScope results.

2. Does all of these triple very high score always do well with the ISEE2 machine and vice versa?

Absolutely NOT. As magnum properly pointed out this is a completely different optical analysis. I have had the opportunity to test and analyze many diamonds (H&A & non) that do outstanding on the Brillancescope and not so good on the Isee2 and vice versa. Some of this is discussed and demonstrated in our tutorial on the subject. It is the rarest of H&A cuts that get the highest results on both technologies. A characteristic that will be part of what will constitute our signature line once we get that rolling.

Hope that helps.

----------------

Rhino,
I'm sure you had a few that scores very high on both machines. Do you still have a sarin report on this type of stone that you can post? Just curious what the numbers look like.

 

[Rhino]

Hi Vtigger,




I am sorry but your answer can not be provided with basic Sarin measurements. Take for example these 2 stones. Both are *very similar* crown/pavilion/table data. Stone #1 here has 34.2 crown angles, 40.7 pavilion angles and 55% table. Stone #2 has 34.4 crown angles, 40.8 pavilion angles and 55.8% table. Both stones would score similar HCA scores and both of these happen to BOTH be H&A diamonds in what I would consider the most cherry combination of proportions (55-56 tables, crown angles between 34-34.5, pavilion angles between 40.7-40.9) continued...




/idealbb/files/br127dvs2sarin.gif/idealbb/files/br105evvs2sarin.gif


So while both of these diamonds have very similar proportions both H&A stones have very different optics.


Here are LightScope results on both. One displays more pale reds than the other while the other shows a greater saturation of dark reds throughout the stone and especially in the most important location ... under the table. This information can not be assessed with the basic Sarin. Important data such as the variances, twist, lower girdle facets, star facets and upper girdles must also be known. It is interesting how 2 diamonds with very similar Sarin dimensions can get such varying optical results but now you might realize why I do not rely on Sarin information alone when we make our purchasing decisions.




/idealbb/files/127dvs2ls2.jpg/idealbb/files/105EVVS1-LTSC.jpg




Obviously the stone on the left has the lower optical results. (low) High in white light, Very High in colored light return and high in scintillation. If memory serves me right this one got somewhere between an 8.9 - 9.1 via Isee2. The stone on the right is a triple VH via B'scope and a 9.8 Isee2. It's optical design is 2nd to none in the realm of H&A cuts and is the best that we get to examine in our lab. I've tried to duplicate these images with an IdealScope and a FireScope but so far can only do so with our LightScope as it shows the most intense level of detail among the red reflectors I've tried. I can't link you to these individual stones here on the forum but if you'd like to see the rest of the details drop me an email.




Kind regards,