GemEX reports

[Lysias]

Wow, I have learned so much in so little time reading these forums and I''d like to move beyond the lurking stage

I''m looking to buy my first diamond for my girlfriend in the next 3-4 weeks. I''ve been to some B&M stores and only now am I realizing how much I have to learn. One store had me hooked on the Leo diamond (technically it was the Leo Artisan, which rates higher on fire and other categories) and GemEX brilliancy reports. However when I look around the forums no one seems to mention GemEX much. The scientist in me says that this is a perfectly objective way to measure brilliance in a diamond, but I''m wondering if the conditions are somewhat artificial. And if GemEX is so reliable then why don''t more vendors use them? I''ve only looked into Whiteflash so far and I love their prices and all the certifications and images they show, but it''s hard to compare to the B&M stones when everyone is using a different test.

So, in conclusion, is GemEX as important as they might portray themselves?

 

[stone-cold11]

GOG uses them.

I remember that GIA was offered GemEx and decided against it because the results are not repeatable, in that the same stone can have different results on different runs.

 

[Lysias]

But will the report correlate with actual brilliance and fire in everyday lighting?

 

[stone-cold11]

Which result is the question to ask if every run results in a different result?

 

[Lysias]

I guess that is the key question. Do you have a link or reference to the variability in their tests?

 

[stone-cold11]

From WF.

http://www.whiteflash.com/diamonds_info/t/faq.aspx?articleid=404&zoneid=6

 

[Rhino]

Hi Lysias,

While the GemEx BrillianceScope has certain limitations there is most definitely objective analysis that it provides in way of its results. Most stores or places that utilize the technology may not comprehend fully what it is and isn''t saying but diamonds that score great results on the technology, you can rest assured the diaimond will *excel* in the lighting environment it is being tested in (that being spot lighting). I too am scientifically oriented and utilize the technology because it does offer an objective, non biased and computerized way to measure aspects of light performance. Early in my Internet career we utilized it in helping us select what would become our signature inventory as diamonds must meet certain minimum results to qualify.

I have written a couple of articles discussing both the pros and cons of the technology and can answer most questions concerning it.

Regards,

 

[Lysias]

@Stonecold: I found a more thorough assessment of WF's view on BrillianceScope http://www.whiteflash.com/diamonds_info/t/all_about.aspx?articleid=668&zoneid=22

@Rhino: From your article on GOG about the Jubilee I could guess that you enjoy the Brilliancescope

I guess my great dilemma is when I'm looking at online stores and can't see the diamond in person, what emphasis do you place on each test?

 

[Rhino]

Date: 11/17/2009 7:54:07 PM
Author: Lysias
@Stonecold: I found a more thorough assessment of WF''s view on BrillianceScope http://www.whiteflash.com/diamonds_info/t/all_about.aspx?articleid=668&zoneid=22

@Rhino: From your article on GOG about the Jubilee I could guess that you enjoy the Brilliancescope

I guess my great dilemma is when I''m looking at online stores and can''t see the diamond in person, what emphasis do you place on each test?

Good question Lysias. I look at each test we perform as one part of a whole in the totality of our optical exams.

When it comes to a digital/optical exams (as opposed to an analog optical exam) the BrillianceScope is IMO one of the best tools available for objectively showing how a modern faceted round diamond will appear in spot lighting (which shows fire/dispersion and sparkle scintillation). It is very hard on grading leakage and other certain characteristics (such as heavy painting) can be detected in the images it generates.

While I utilize the technology to objectively show certain optical characteristics in the diamonds we feature I am also careful to point out to our clients not to get caught up in what is called "analysis paralysis". Ie. I can show 2 H&A round brilliant cuts, one get a high/very high/high and one get triple VH and the two diamonds look identical. I can also show example where they will not. I''ve considered dropping it a number of times but still provide the information in our Appraisal Reports to arm our clients with another piece of data to demonstrate the scrutiny to which their diamond has been selected.

BTW ... if you are going to give weight to its exam there is

a. Leo diamonds that vary in their results and
b. Other data which is IMO equally if not more important to consider when selecting a diamond for optical properties.

The Leo has more pavilion mains that a traditional round as well as thinner mains resulting in a more splintery appearance. One of the first pieces of data we like to learn from people we are helping is do they indeed enjoy this more splintery appearance or perhaps a bigger/wider flash of light coming from within the diamond or perhaps something in between? Rounds are cut to a variety of appearances and the nature of their reflections change with facet designs and proportion sets.

Good luck in your hunt.