Laboratory Cut Grades: What the report doesn’t show

[strmrdr]

Date: 5/29/2009 4:02:59 PM
Author: Regular Guy

I wonder if two different things need to be teased out?


a) whether the characteristic of fire is particular to the interaction with the individual, which I think you are saying, and where this is less an inherent native characteristic of a diamond


b) or...to the extent it may be an identifiable characteristic, associated with some properties (as for example, as is frequently recognized here, described by Garry, that, for example, a smaller table will typically be more associated with fire...all things being equal)...that it may be more difficult to capture with by way of a device to measure this directly, rather than indirectly....which I think Serg is saying?


There may be 4 things here, but you get the idea.


Thanks for reviewing...

a: the 3 biggest things affecting apparent fire are LVV:
Lighting
Viewer
Virtual facets
Yes the diamond itself is third on the list.

Something that is going to very very important is the My 3 person rule:
3 people standing side by side looking at a diamond the center person is holding are looking at totally different virtual facets and a totally different lighting environment.
Contrast this with the cyclops reflector view with a fixed viewing environment and you get an idea of the scope of the problem to be solved.

b: A small table and high crown are important to fire in a few different ways.
This is more apparent in step cuts because the raw light return power of a RB overshadows it in a well cut RB.
1: increases virtual facet number
2: decreases average virtual facet size while maintaining large and med VF's (adding more facets decreases average virtual facet size but also means much less med and large virtual facets, this can be a good thing in large diamonds not so good in more common sizes)
3: increases the angles a diamond draws light from, and return light to.
4: increases the apparent effects of dispersion.

 

[John P]

Date: 5/31/2009 11:20:01 AM
Author: strmrdr

Date: 5/29/2009 4:02:59 PM
Author: Regular Guy

I wonder if two different things need to be teased out?

a) whether the characteristic of fire is particular to the interaction with the individual, which I think you are saying, and where this is less an inherent native characteristic of a diamond

b) or...to the extent it may be an identifiable characteristic, associated with some properties (as for example, as is frequently recognized here, described by Garry, that, for example, a smaller table will typically be more associated with fire...all things being equal)...that it may be more difficult to capture with by way of a device to measure this directly, rather than indirectly....which I think Serg is saying?

There may be 4 things here, but you get the idea.

Thanks for reviewing...

a: the 3 biggest things affecting apparent fire are LVV:
Lighting
Viewer
Virtual facets
Yes the diamond itself is third on the list.

Something that is going to very very important is the My 3 person rule:
3 people standing side by side looking at a diamond the center person is holding are looking at totally different virtual facets and a totally different lighting environment.
Contrast this with the cyclops reflector view with a fixed viewing environment and you get an idea of the scope of the problem to be solved.

b: A small table and high crown are important to fire in a few different ways.
This is more apparent in step cuts because the raw light return power of a RB overshadows it in a well cut RB.
1: increases virtual facet number
2: decreases average virtual facet size while maintaining large and med VF's (adding more facets decreases average virtual facet size but also means much less med and large virtual facets, this can be a good thing in large diamonds not so good in more common sizes)
3: increases the angles a diamond draws light from, and return light to.
4: increases the apparent effects of dispersion.

Ira (red text) it's certainly both as Karl points out, with even more to be considered.

I mused above that we're moving towards a day where modeling will become harmonized for use in both cut design and future assessment standardization... Even today there are some pretty intense real-world applications. Both Octonus and Sarin have machines being used in cutting houses to analyze rough, map inclusions and calculate cutting options. In the most sophisticated applications prospective shapes are considered and the planner can see predicted levels of brightness, color saturation and contrast in different lighting conditions; allowing efficient optimization of the subject rough.

The day when such upstream technologies handshake (with a firm grip?) with downstream analysis will eventually come. One bugaboo is the disagreement about direct assessment versus modeling. I think we have reached some limitations with DA (brightness, leakage, contrast). No problem, as we have come a long way; it's all well and good.

For the long-term my feeling is that - just as practical upstream rough planning deals with projections and analysis of potential - assessment of dispersion and scintillation will be based on projections and potential in the macro, rather than direct assessment confined to one metric.

 

[John P]

Date: 5/31/2009 10:11:05 AM
Author: gwendolyn

What a fantastic article, John! The information is educational and precise without being full of confusing jargon, and the photographs perfectly highlight the range of possible looks in rounds. Plus, you worked in a drum reference! You get an A+.

Glad you liked it.

Thank you kindly, G.

 

[Judah Gutwein]

John,

Great article!

 

[bright&shiny]

What a fantastic article! As a consumer - this is exactly one of my frustrations. This "c" is not standardized in such a way that I understand what the stone will look like based on the cut classifications. Having been looking for stones for the past few months, this has been the singularly most difficult aspect to describe to the woefully under-educated retailers in our area.  However, when we brought along our ASET and IdealScope gadgets we were able to show them what we meant about the variance of light play between stones with the same ''cut'' classification. Now I can show people exactly what I mean by showing them your article.

By the way, I know I''m just a consumer - beginning my education on the new tools available etc.... but I have to say that resisting the technology for reflectors and the data they provide reminds me of GM a few years ago. When I first worked there (yes, I escaped before it got bad) they hated Consumer Reports because they didn''t rate their cars well. They failed to realize, until very late in the game, that regardless of their feelings about the magazine and their testing methods, it had an enormous impact on purchasing. I think that will be the case with these tools simply because it provides a way to help us go beyond the sales pitch - so we can make decisions we feel good about.

Not only have I found those tools invaluable for sorting through the stones to find the ones I''d like to consider, after conducting a few experiments to select with out the tools and then review with them - my eye and the tools were completely aligned. I just used to tools to help narrow the field for the subjective eye part of the project (which one sings). If I can do that, I expect most other folks can, as well.

Now, if we could only have a tool to help select mattresses and sort through that mess....

 

[John P]

Date: 6/8/2009 5:24:07 PM
Author: Judah Gutwein

John,

Great article!

Thanks & a tip of the hat, Judah.

Date: 6/8/2009 10:28:51 PM
Author: bright&shiny

What a fantastic article! As a consumer - this is exactly one of my frustrations. This 'c' is not standardized in such a way that I understand what the stone will look like based on the cut classifications. Having been looking for stones for the past few months, this has been the singularly most difficult aspect to describe to the woefully under-educated retailers in our area. However, when we brought along our ASET and IdealScope gadgets we were able to show them what we meant about the variance of light play between stones with the same 'cut' classification. Now I can show people exactly what I mean by showing them your article.

It's interesting that instruments used to assess the other Cs are universal. Methods may vary but labs, appraisers and (educated) jewelers alike are familiar with scales, master sets and microscopes. There is a glaring lack of presence of instruments used to demonstrate differences in the way a diamond has been cut. Why do you think this is?

By the way, I know I'm just a consumer - beginning my education on the new tools available etc.... but I have to say that resisting the technology for reflectors and the data they provide reminds me of GM a few years ago. When I first worked there (yes, I escaped before it got bad) they hated Consumer Reports because they didn't rate their cars well. They failed to realize, until very late in the game, that regardless of their feelings about the magazine and their testing methods, it had an enormous impact on purchasing. I think that will be the case with these tools simply because it provides a way to help us go beyond the sales pitch - so we can make decisions we feel good about.

Not only have I found those tools invaluable for sorting through the stones to find the ones I'd like to consider, after conducting a few experiments to select with out the tools and then review with them - my eye and the tools were completely aligned. I just used to tools to help narrow the field for the subjective eye part of the project (which one sings). If I can do that, I expect most other folks can, as well.

Bravo. There is no doubt the 'gadgets' you name demonstrate the science of angular spectrum and where a diamond is drawing - and returning - light. What do you think would make dealers in traditional stores more inclined to use them as a source of information; like using a microscope when explaining clarity? Ex: A tour of a diamond's natural characteristics via wedge - allowing the client to manipulate zoom & lighting - can be a powerful education & trust-building exercise.

 

[bright&shiny]

Re:

"However, when we brought along our ASET and IdealScope gadgets we were able to show them what we meant about the variance of light play between stones with the same ''cut'' classification. Now I can show people exactly what I mean by showing them your article."

It''s interesting that instruments used to assess the other Cs are universal. Methods may vary but labs, appraisers and (educated) jewelers alike are familiar with scales, master sets and microscopes. There is a glaring lack of presence of instruments used to demonstrate differences in the way a diamond has been cut. Why do you think this is?

" I just used to tools to help narrow the field for the subjective eye part of the project (which one sings). If I can do that, I expect most other folks can, as well."

Bravo. There is no doubt the ''gadgets'' you name demonstrate the science of angular spectrum and where a diamond is drawing - and returning - light. What do you think would make dealers in traditional stores more inclined to use them as a source of information; like using a microscope when explaining clarity? Ex: A tour of a diamond''s natural characteristics via wedge - allowing the client to manipulate zoom & lighting - can be a powerful education & trust-building exercise.

John,
Because I''m not in the industry - just a happy consumer - I''m not sure I know these answers, but I''ll give you my thoughts anyway.

Regarding the lack of standardized tools & helping traditional stores to use the technology: I think the tools exist at the moment - ASET and Ideal/Fire Scopes. I can think of no reason not to have them widely available save one: it doesn''t help jewelers sell the stones they have in stock or generally order. Most of the retailers in my experience, do not carry a wide selection of stones, and most do not have a selection of stones that would have favorable light-capture and return images. In addition, the tools I have seen are for loose stones - many retailers have the stones set already.

The only incentive I can think of for retailers and other jewelers to adopt the tools and information already available is the bottom line: will it make them more money? If they sell stones that will provide great (or even a range) of light images, they will do well. Sadly, it seems so many operate on the margin of stone quality (looks nice, but isn''t great), these tools won''t help them sell the stones they need to sell (high margin). What will they do with the stones already in inventory? Of course, there will always be a market for a lesser but larger stone, as long as it is pleasing to look at (however one defines pleasing), but who wants to intentionally buy a lesser stone? Marketing encourages exactly the opposite.

It is clear the industry has done a formidable job ''educating'' the consumer in the usual c''s. Adding another c (cut) upends the cart. Now the previous mantras are less important - so what will they do with all the marketing materials and how will they manage the expectations of the folks for whom this is new information. It might also affect the value of previously purchased stones (I''m thinking of the ''trade-in'' programs I''ve heard about). If you purchased a flawless, colorless stone, but it isn''t cut as well as a stone with the same specifications, what happens to the value of the lesser-cut stone? Given the economy, that''s a big consideration

Now, for the shops that can afford to shift their inventory and grab a bit of the new market (those interested in cut), they have nothing to loose by bringing in the technology and education. We worked with the several on-line sites to view stones - and we visited one of their retail shops. It was a fantastic experience and built trust instantly. We were able to use all the tools, including the GIA diamond dock - which allowed us to make comparisons between many stones. The final line up was selected using the tools - and the ''eye'' test narrowed it down to 2 or 3 that were all beautiful and unique.

What we really need is a revolution - but it will leave a lot a waste in its wake: all the stones that don''t make the ''cut''. Pun intended. Sorry. Enough rambling from a newbie.