DiamCalc Anyone ?

[Iceberg]

Hi !

I was wondering if anyone would do me a HUGE favor and run my diamond through DiamCalc and GemAdviser !

All comments will be appreciated.

Here are the specs;

Round Brilliant: 5.12 x 5.16 x 3.17 mm ( VS2, G ) .512 cts
Depth: 61.6%
Table: 56%
Crown angle: 34.6
Pavilion angle: 40.8
Pointed culet
Girdle is faceted 1.4% - 3.9%
NO fluorescence

Thank you for your time and effort

 

[Iceberg]

I forgot !!!!

Girdle is Thin to medium, faceted
Ideal symmetry and and polish

Paul

 

[Rhino]

Hi Iceberg,

Do you have lower half and star info?

 

[Rhino]

If not I can generate some graphics for you showing you the various appearances this diamond can take depending on minor facet construction. Would you want to see red reflector views (similar to LightScope or IdealScope) or bright white lighting views? Let me say you're off to a good start with those angles btw.

Regards,

 

[Iceberg]

You got me Rhino.

Lower half and star info??? Hummmm I wish I knew what you were requesting. Where can I find such info ? If not available, is this a problem ?

Thank you for your reply !

Paul

 

[Iceberg]

Boy, you sure are a pro.

Red reflector views (similar to LightScope or IdealScope) or bright white lighting views?

I don''t know !! You seem like an expert. You choose for me. I''ll trust your call.

Paul

 

[Rhino]

Ok... store is now closed but I''ll put in a little ot for ya.

Briefly ... lower halves (also known as lower girdle facets) comprise 16 facets on the pavilion (bottom side of the stone) out of 24 facets. Measurements on these facets can greatly affect the appearance of the diamond in question. Star facets ... there are 8 of them that surround the table facet. Knowledge of the measurements of these facets is important in determining the accurate appearance of a diamond. Sadly most Sarin''s give the results of only 17 out of 57 facets. I''ll get the pix up for ya in a sec...

 

[Iceberg]

Thank you are very caring. I appreciate the time (overtime) you are giving me. I applaud you effort.

Paul

 

[Rhino]

Date: 9/8/2005 9:30:53 PM
Author: Iceberg
Thank you are very caring. I appreciate the time (overtime) you are giving me. I applaud you effort.

Paul

bah ... sorry I mentioned it but thank you.

Here ya go. I took the measurements you gave from the Sarin and only altered the 16 lower girdle facets. If you''d like to learn more about these facets and how they impact diamond appearance let me know. I altered these because of all the facets that are usually not given on Sarin reports, these facets impact appearance most.

These pictures assume perfect optical symmetry so it is possible the stone''s symmetry pattern may not be as symmetrical as these pictures. These are only 4 out of many possibilities. As I said though ... you''re off to a great start with those angles. It''s certainly a stone worth further investigation. I''m about to head home for the night but when I get in tomorrow I''ll check again on this thread if there is any assistance I can offer. Hope this helps and btw ... I love your screenname.

Appropriate for the task at hand I''d say.

 

[Rhino]

btw ... if you wanna have a little fun ... download the free software at this link open up the test stone and play. There are appraisers here who can generate models that you can load into this software and "virtually" see the diamond. It''s pretty cool and offers some interesting views. The kind folks here can point you to appraisers who can generate the models too. I would but wife is waiting for me.

http://www.octonus.com/download/GemAdviserSetup.exe

Good luck with this and cya tomorrow iceberg.

Kind regards,

 

[Iceberg]

Thanks !!!

The diamond is cut with all proportions specifications within the AGS 0-cut (Ideal) grade and has polish and symmetry graded Ideal with Excellent symmetry.

HCA score is 1.3 ( excellent Light Return, Fire and Scintillation....but only very good spread)

.512 , VS2 , G

In your opinion, should I go ahead and purchase at 1800$ ?

Reason I''m asking ???? I have just read a posting by Garry Holloway which led me to goodoldgold.com.

I punched in VS2 G .52........and got an HCA of .4 for the 2 stones offered so, I got worried regarding MY newly purchased stone.

Should I simply relax and believe in the fact that I have found a good diamond.....I sure hope you can be unbiased ''cause, I noticed that you Rhino worked for goodoldgold !!!! Arghhhhhh

I wish I would of known about your site earlier. When I saw the stats, I yelled '' Garry !!! why didn''t you give me this info yesterday, BEFORE I bought my diamond ??? '' Although, even after having seen the stats ( HCA = .4 ), not seeing any grading reports for the posted diamonds did put me at ease...it''s the only bit that allows me to breathe. HCA is fine as an additional tool but, seeing grading reports greatly supports one''s purchase decision that is, in my opinion.

Phew...................


Paul

 

[Rhino]

Burnin the oil here so thought I'd respond.

Date: 9/8/2005 10:11:26 PM
Author: Iceberg
Thanks !!!

The diamond is cut with all proportions specifications within the AGS 0-cut (Ideal) grade and has polish and symmetry graded Ideal with Excellent symmetry.

HCA score is 1.3 ( excellent Light Return, Fire and Scintillation....but only very good spread)

.512 , VS2 , G

Don't take the "very good" spread as a negative. Garry, the designer of the software penalizes stones with a depth that's greater than ... 60.4 is it? (Garry correct me if I'm wrong). The stone you listed has a depth of 61.6% which just about any appraiser worth is weight in salt will tell you that is just fine and they would be 100% correct. This is one area (amongst many haha) where Garry is in disagreement with popular opinion. Don't take that statement wrong. Garry is a very respected mate in the trade and I would be included in that respect for him.

In your opinion, should I go ahead and purchase at 1800$ ?

Reason I'm asking ???? I have just read a posting by Garry Holloway which led me to goodoldgold.com.

I punched in VS2 G .52........and got an HCA of .4 for the 2 stones offered so, I got worried regarding MY newly purchased stone.

What a bum that Garry is. See that ... he makes all kinds of mistakes.

What's funny about your comment Iceberg is YOU SHOULDN'T BE WORRIED because a .4 usually results in a sucky diamond.

Well ... perhaps sucky is too strong a word but I generally would not recommend one for an engagement ring. I know you're scratching your head now. You see ... I've been buying and selling these things for a little while now and have studied TO DEATH and examined stones with HCA scores all over the map. I would recommend a 1.3 over a .4 if that was all the information I had on the 2 stones. You may ask ... why would I not recommend my own GOG stone over the one you are considering? Because I know from experience that a .4 diamond on the HCA would best be served in an earring rather than an engagement ring and that would be my advice to you even if you were comparing my stone with another. So ... don't be worried.

I bet you found that stone on our search engine and not our in house inventory.

Should I simply relax and believe in the fact that I have found a good diamond.....I sure hope you can be unbiased 'cause, I noticed that you Rhino worked for goodoldgold !!!! Arghhhhhh

LOL. I would assume most people who read these forums would think I am biased since I am a seller of diamonds and I'm sure in my writings this can be perceived. I would be a liar if I didn't tell you I enjoy making sales as a result of serving people here, however I will never knowingly risk the integrity of the information I share with the consumers who come to this forum. Hence my recommendation of a 1.3 over a .4 you saw on our site. If I ever risked my integrity for sharing factual information my opinion here would be ripped to shreds by other experts who could prove I was right or wrong. That doesnt' necessarily mean we are all in agreement on all issues either. We're all at different stages in our walk through diamond-land. I make every effort to try to be as careful as possible when sharing information that affects a person's wallet. That's why I shared that even among the 4 examples I posted in that graphic for ya, they are only 4 of MANY combinations you could possibly have. Btw a .4 on the HCA would appear darker and that phenomena would also show up in the graphics I posted. I'd generate an image now but my software is on the other comp.

I wish I would of known about your site earlier. When I saw the stats, I yelled ' Garry !!! why didn't you give me this info yesterday, BEFORE I bought my diamond ??? ' Although, even after having seen the stats ( HCA = .4 ), not seeing any grading reports for the posted diamonds did put me at ease...it's the only bit that allows me to breathe. HCA is fine as an additional tool but, seeing grading reports greatly supports one's purchase decision that is, in my opinion.

Phew...................


Paul

LOL. I'm sure you'll be fine iceberg.

FYI, most stones that *we* see most often, among the graphics I posted fall within the 75-80 lower girdle facet range so there is a good chance your's may too.

Keep us posted on your progress!

Are you going to have it appraised with one of the PS appraisers here? It would be interesting to see a model of the actual stone.

Warm regards,

 

[Iceberg]

Hi.

You did indeed burn the midnight oil !!!

You have earned all of my respect Rhino. You truly have shown integrity and that my friend is, unfortunately, a rare asset these days.

I appreciated your explanations. Still, one more question ( ya right ), you mentioned that my 1.3 would be better for my future e-ring than the .4

You have me confused since I believed that the HCA gave a score based on an analysis of a diamond''s parameters compared to Tolkowsky''s Ideal cut parameters. Consequently, I believed that should a diamond fall within the TIC range, it will have enhanced beauty (based on Tolkowsky''s study).

So tell me, what would be the prefered HCA scores to look for when buying a diamond for a e-ring ? I have read ( I did, I did ) that most diamonds which fall in the TIC range will be between 1 and 2. One must not forget that BELOW 2 is prefered ! Rhino, I thought that getting excellent for (light return, fire, scintilation and spread) was the goal.

I apologize for all this but your views and explanations fascinate me. I''m learning and I value the knowledge. I hope that Garry can at one time include his grain of salt in this ''valuable'' discussion.

Kind regards,

Paul

 

[Garry H (Cut Nut)]

Garry''s grain of salt is too influenced by his Friday night drop of wine to be constructive

But i can say that HCA owes nothing to Tolkowsky

 

[Rhino]

Date: 9/9/2005 9:26:58 AM
Author: Garry H (Cut Nut)
Garry''s grain of salt is too influenced by his Friday night drop of wine to be constructive

But i can say that HCA owes nothing to Tolkowsky

Hey ... I wish I were alongside ya sharing that drop bro!

 

[Rhino]

Date: 9/9/2005 7:14:45 AM
Author: Iceberg

I appreciated your explanations. Still, one more question ( ya right ), you mentioned that my 1.3 would be better for my future e-ring than the .4

You have me confused since I believed that the HCA gave a score based on an analysis of a diamond''s parameters compared to Tolkowsky''s Ideal cut parameters. Consequently, I believed that should a diamond fall within the TIC range, it will have enhanced beauty (based on Tolkowsky''s study).

So tell me, what would be the prefered HCA scores to look for when buying a diamond for a e-ring ? I have read ( I did, I did ) that most diamonds which fall in the TIC range will be between 1 and 2. One must not forget that BELOW 2 is prefered ! Rhino, I thought that getting excellent for (light return, fire, scintilation and spread) was the goal.

I apologize for all this but your views and explanations fascinate me. I''m learning and I value the knowledge. I hope that Garry can at one time include his grain of salt in this ''valuable'' discussion.

Hi Ice,


Thank you for the kind words. I appreciate that. In answer to your further questions ...

The HCA is a tool primarily used to weed out what we would refer to as "steep/deep" combinations of angles. Diamonds that have steep/deep angles produce too much light leakage and Garry (as well as some others cut geeks around here, including myself) are on a kind of personal crusade to see poop cut diamonds eliminated and/or reduced.

And by golly we see it happening on a grander scale than perhaps a couple of years ago! (Let''s drink to that too Garry!

).
Garry is one of the first professionals in the trade to have received a device which is called a "FireScope(tm)". A FireScope is a reflector based technology that can show a gemologist (or even a layman for that matter) which facets within the diamond are functioning as either mirros (reflectors of light) or windows (leakers of light). The attached graphic is a photograph I have taken of both for your edification. The white represents leakage, red and black light return. We feature a more indepth tutorial on this on our website of you''d like to learn more with many photographs and illustrations of various qualities.

So ... one of the strengths of the HCA is that of weeding out steep/deep combos. Those will generally score over a 2.0 on the HCA and rightfully so.

One of Garry''s personal preferences is that for stones that would fall on the opposite end of the spectrum or what I would refer to as "shallow/shallow" combinations. Shallow combinations will appear to have a very solid image under reflector technologies however one of the weakness'' of reflector technologies is that they do not show the consumer an accurate portrayal of how these particular combinations appear to the human eye. Under a FireScope (or other similar reflector) they would appera to be fine, however upon examination they display a darker appearance due to too much head obstruction. This is why I said these would be better for earrings where there is typically more distance between the viewers eyes and the diamonds in most viewing circumstances (hence less head obstruction). I would also say that if I had to choose between a steep/deep vs a shallow/shallow I''d take the shallow any day however if there are other choices (like for example the one you are considering) I would avoid both and get the best possible cut I could. I have examples of shallow/shallows I can link you to for education but am not permitted to do so here.

It is these shallow/shallow combos that generally score around .8 and under on the HCA although I''ve seen combos up to 1.0. I have also seen stones that were just fine with those scores which is why each diamond must be looked at on an individual basis. The HCA is not designed to make purchasing decisions by Ice. It is to be used as a preliminary tool for weeding out certain combos of angles for further investigation. Consultation with a professional is recommended *at all times* as there are also some other basic assumptions with HCA results that may not reflect actual appearance (like optical symmetry). So the HCA software does reflect some of Garry''s personal preferences which other professionals and consumers do not prefer. Some would consider this a weakness of the HCA. I am personally in the process of writing a comprehensive article on this very subject which will be published in the near future to help consumers, who are consulting tools like the HCA and reflector images to understand both their strengths and their weakness''. I recently published a thread on the forum introducing a new discovery we have made with reflectors that shows some tremendous detail regarding the optical design of diamonds, but admittedly its pretty deep and has to do with the twisting of facets. LOL... lets not go there for now though.

So in summary... stones that get penalized for spread happen to be some of the most beautiful rocks (under 2.0). As crown/pavilion angles get more shallow the better the HCA score ... however according to many professionals, the lower the number (like around .8 and under) the more the stone begins to take a curve that is also not desireable.

I hope that helps Ice.

Kind regards,

 

[Iceberg]

Hello Rhino.

WOW...you are meticulous (I guess it must come from you work habits)

Thanks a million for your time and exhaustive information.

I guess that my diamond :

AGS report done on August 19th (New AGS report since June 1st 2005)

AGS Ideal 0 (Light performance 0, Proportion factors 0 and Finish 0(ideal symmetry and polish) AND an HCA score of 1.3

Tell me Rhino, will one honestly be able to tell (naked eye) that my diamond is of such an IDEAL cut ? Moreover, an HCA score ( 1.3 )telling me that I will have excellent light return, fire and scintillation...will that show ? OR you can''t really tell unless one looks under a microscope ?

I am well aware that everything is all in the cut. But can you truly tell the difference ? I mean, will a perfect stranger on a bus see my girl''s diamond and notice the diamond''s quality ? EVEN if it''s only a .51? (I could not afford a larger stone). Don''t lie, be honest !!!! Well, be yourself.

Thank you my friend. I can honestly tell you that, in the future, I will look you up BEFORE I purchase. : )

Paul

 

[belle]

i''m no rhino, but i''ll throw in my 2 cents....

yes, others will be able to tell the quality of your diamond. people that know a little about diamonds will recognize immediately the superior cut. those that don''t know so much about diamonds will notice that your stone has awesome sparkle and crispness. they may not understand why (this is where you can give them some quick cut education) but they will realize that there is something special about it. even at .51cts. your diamond will appear larger than most of the pedestrian cut diamonds you will see everyday. the superior cut will allow more light return and not look ''dead''. cheers to well cut diamonds!

 

[Garry H (Cut Nut)]

Date: 9/9/2005 5:32:43 PM
Author: Iceberg
Hello Rhino.

will one honestly be able to tell (naked eye) that my diamond is of such an IDEAL cut ? Moreover, an HCA score ( 1.3 )telling me that I will have excellent light return, fire and scintillation...will that show ? OR you can''t really tell unless one looks under a microscope ?
I think it would be impossible that a less than beautiful round diamond would be given AGS''s new zero grade.

I am well aware that everything is all in the cut. But can you truly tell the difference ? I mean, will a perfect stranger on a bus see my girl''s diamond and notice the diamond''s quality ? The lower scoring HCA stones will possibly turn the most heads on the bus. but if you have a large dark hat on, and look at your diamond from close up, then many of the HCA between 1 and 2 in the upper range of the red zone in the HCA chart will look better IF THEY ARE CLEAN.
Paul

 

[Rhino]

Hey Paul,

Heh... I think I"ve exhausted as much information as I could based on the info you had. It is nice that it was accompanied with a newer AGS report but even if it wasn't, you've got the basics there for a beaut and many stones do not even have the basics that yours does. The only possible difference could be in the optical symmetry which I would have had to inspect first hand. Below is an image of 2 AGS Ideal cuts but with drastically different optical symmetry. Optical symmetry is a factor that AGS does not take into account that some of us do when it comes to grading cut. In either case both are nice diamonds, just different looking appearances. Hey ... DON'T SWEAT IT. Both are beautiful!

Let me say this though in answer to your question... YES people will be able to see the difference in the cut. Even in a .51ct diamond. I love to demonstrate this when folks are here in store. As it was pointed out in another thread here ... size means nothing. Quality means everything and at the end of the day it is cut that impacts the beauty more than anything. You've made a good decision based on the data you had and many folks don't even get that far.

I was a pleasure to meet ya Paul, and if you're ever out in the NY (Long Island) area don't hesitate to stop by and we'll do some good ol NY pizza and shoot the bull over all this. Are you having it appraised with a PS appraiser?

Kind regards,
Jonathan

 

[Garry H (Cut Nut)]

Rhino does the stone on the right have a new or an old AGS 0 certificate?

 

[Rhino]

Date: 9/9/2005 6:10:21 PM
Author: Garry H (Cut Nut)
Rhino does the stone on the right have a new or an old AGS 0 certificate?

Good question. New. You may be a little surprised to see the rest of the stats on that one however I''m about to book out of work for now. If memory recalls it has a pav angle at or over 41

 

[Iceberg]

Rhino...

I was able to get you this. It was done on my diamond. Is this an additional piece of info that enlightens your opinion ?

Paul

 

[Rhino]

GOOD WORK PAUL! You got a GCAL Report! I happen to know Don Palmieri personally, the director of the lab. Good man to deal with. Our Square H&A Jubilee''s are lab graded with him and he guarantee''s his work. You''ve got a stone there Paul I would be proud to represent and looks to be of H&A or near H&A status which is excellent. As you view this diamond alongside others people will see the difference I guarantee ya. Have you downloaded the free Gem Advisor software I linked you to above? If so, when I get up to work tomorrow and as time allows I''ll attempt to create a virtual model for you as close as I can.

CONGRATS!!! Now keep us posted on your proposal.

Best regards,

 

[Iceberg]

Yes I did download the software but, I tried to read the help file as to how to use it (I swear) and, I was lost !!

Moreover, I have uploaded the AGS report. I''ve got such a hard time with these 100kb limits!!! It''s takes me 4-6 attempts everytime to succeed at an upload.

I''m giving ya everything I''ve got ! Took me a month to find my diamond (I''m not B-sssing you). I''m a rookie, can''t get a rock in a rougher state than me. I''m in the pebble category but...I research...Thank God I found PS. PS rocks !!



Paul

=

Buy smart !

 

[Iceberg]

Oh BOY !! Rhino you have just said the magic words and I quote '' You got a GCAL Report! I happen to know Don Palmieri personally, the director of the lab. Good man to deal with. ''

Am I ever glad to hear this. Here''s why. Three weeks ago, I bought a diamond and from the very beginning I was incredibly puzzled at the symmetry GCAL had given on it. please see attached pic.

Here''s a question that no one has been able to answer...yet.

The GCAL report''s Optical Symmetry Analysis that had been done on my newly purchased diamond was NOT giving me peace of mind....at all.

I was puzzled as to why its Optical Symmetry Analysis was so different from all the other diamonds I had looked at. I therefore turned to '' the experts '' in the field of diamonds for an unbiased opinion and, most of all, peace of mind. I asked AGS and, they had no clue. If they don''t, then, as a consumer, I really should not know at all. Moreover, the fact that they did not know worried me a little more. I then sent some twenty e-mails to experts accross North America. Noone could answer my question (half of them refered me to Pricescope). I had writen three e-mails to GCAL and they never wrote back.

Why were the red lines so prominent ? Why is it that all diamonds'' symmetry that I had observed showed the middle of the diamond with a small circle (clear or different shades of blue) with black lines showing symmetry (like spokes of a bicycle wheel) but not intersecting in the middle thus allowing the small circle in the middle to be visible. But in old diamond , you could easily see prominent thick red lines clearly intersecting that middle part. Sorry, I hope you can understand what I''m talking about. The main question is: Why is it so obviously different (red lines being so prominent) from all the other diamonds'' Optical Symmetry Analysis'' ?

Rhino, there are no human on this earth that has given me an answer. I had posted my question on PS but, even with over 200 visits.....NO replies.

SO, I returned the diamond.

I have now found the one I''ve shown you and purchased it.

Jonathan, my friend, why don''t you ask M. Palmieri this ultimate question: What is the explanation for those prominent red lines ???? I''m dying to find out.

Your humble pebble,

Paul

 

[Rhino]

Hey senor,

Managed to break away a bit ... I got your model for ya too. See the attachment.

Date: 9/9/2005 10:29:24 PM
Author: Iceberg
Yes I did download the software but, I tried to read the help file as to how to use it (I swear) and, I was lost !!

LOL... perhaps we can have a "Gem Advisor" lesson here too. I''ll be glad to answer any questions you have about the software insofar as I am able to explain and understand. The developer of it, Sergey, Yuri and the team at Moscow State University frequent this forum as well so if I''m stuck on anything they can help too.

I''m giving ya everything I''ve got ! Took me a month to find my diamond (I''m not B-sssing you). I''m a rookie, can''t get a rock in a rougher state than me. I''m in the pebble category but...I research...Thank God I found PS. PS rocks !!

Paul

=

Buy smart !

Heh... PS does rock. There are many fine folks here and consumers who just LOVE to share their opinions. Most I have met here are very fine and friendly people. I try to stick to the diamond information questions/threads but once in a while get involved in threads with more drama.

Check out the file right below my signature. There''s your model.

Best regards,

 

[Rhino]

Working on the answer to your last post now...

 

[Rhino]

Ok... thought for thought.

Oh BOY !! Rhino you have just said the magic words and I quote '' You got a GCAL Report! I happen to know Don Palmieri personally, the director of the lab. Good man to deal with. ''

Am I ever glad to hear this. Here''s why. Three weeks ago, I bought a diamond and from the very beginning I was incredibly puzzled at the symmetry GCAL had given on it. please see attached pic.

Ok ... this one with "excellent" optical symmetry. I''m with ya so far...

Here''s a question that no one has been able to answer...yet.

The GCAL report''s Optical Symmetry Analysis that had been done on my newly purchased diamond was NOT giving me peace of mind....at all.

I was puzzled as to why its Optical Symmetry Analysis was so different from all the other diamonds I had looked at.

LOL... probably becuase their optical symmetry was akin to the picture I had posted in this thread of the 2 ideal cuts side by side. One has awesome optical symmetry the other I would consider to be "chaotic". Just curious ... was the optical symmetry of a more inferior grade on all the others you were viewing? Perhaps this is the first one with excellent optical symmetry you had seen. These are the more rare breed of cut.

I therefore turned to '' the experts '' in the field of diamonds for an unbiased opinion and, most of all, peace of mind. I asked AGS and, they had no clue. If they don''t, then, as a consumer, I really should not know at all. Moreover, the fact that they did not know worried me a little more. I then sent some twenty e-mails to experts accross North America. Noone could answer my question (half of them refered me to Pricescope). I had writen three e-mails to GCAL and they never wrote back.

Hrm.

Don''t know what to tell ya there. Since we are a bricks and mortar store with a strong internet presence we try and keep on top of our emails on an hourlly to daily basis (as well as the forum, except for when we''re closed of course). AGS and GCAL are not web based business'' so I''m sure they don''t check their email as often as our staff does. Heh... I have been known to make mistakes from time to time not getting back quick enough to email too so I can sympathize.

Why were the red lines so prominent ? Why is it that all diamonds'' symmetry that I had observed showed the middle of the diamond with a small circle (clear or different shades of blue) with black lines showing symmetry (like spokes of a bicycle wheel) but not intersecting in the middle thus allowing the small circle in the middle to be visible. But in old diamond , you could easily see prominent thick red lines clearly intersecting that middle part. Sorry, I hope you can understand what I''m talking about. The main question is: Why is it so obviously different (red lines being so prominent) from all the other diamonds'' Optical Symmetry Analysis'' ?

This is because you are asking questions about an analysis that is performed by few in this country. The analysis of optical symmetry. AGS does not perform it. GIA does not perform it. The new cut grading schemes unfortunately will not be taking it into consideration in their new lab reports (both AGS and GIA). No major gem lab that I know of does except for perhaps GCAL. You happen to be talking to someone who has studied this very subject for quite a number of years now ... ever since I was introduced to it in 2000 by a factory that specializes in its art and cuts their diamonds to very exacting specifications with OPTICAL SYMMETRY at the forefront of its mind. Although I do not carry the product currently I will be candid and share with you that it is the EightStar Diamond Company. They cut stones for optical symmetry at the expense of lab graded polish and symmetry and I was trained with reflector technology by the president himself, Richard Von Sternberg. The launching pad to my education on this subject was by a factory that many would deem as "the authority" in optical symmetry, however my education on the subject has expaned way past what I had initially learned and I''ve been able to answer many questions I had which I did not know the answers too through these reflector based technologies, which I work with on a daily basis.

The phenomena you are describing sounds pretty much like the comparisons in the graphic below. Let me know if we''re on the same page or not.

While I am not familiar with the exact color scheme or angular spectrum that GCAL is using in their photographs (btw, they should REALLY have a tutorial on their website explaining it) I have generated colored symmetry images that are similar but not identical to that of GCAL. These are actually AGS'' new ASET views. My question to you Paul ... is this basically the type of comparison you are talking about? Note the center circle in the image on the right is easier to resolve while the circle in the one on the left is well ... chaotic. Is this what you were seeing or is this what you are trying to communicate in what you were comparing? BTW both of these stones are AGS ideals.

I look forward to hearing back from ya.

Regards,
Jonathan

 

[Rhino]

btw... here are the same 2 stones, different reflector (red reflector), actual photographs. Hope this helps.