GIA "excellent" -- why doesn''t it "add up?"

[Garry H (Cut Nut)]

Date: 4/20/2006 6:45:58 PM
Author: Rhino

Date: 4/20/2006 3:04:13 AM
Author: Garry H (Cut Nut)

Date: 4/19/2006 8:56:42 PM
Author: Rhino


At first when I saw what GIA was doingwith the rounding I was concerned as well. I am a stickler for detail and to me, the more exacting the better. Once I began to communicate with the research gemologists at GIA I understood their reasoning for the rounding and when I considered real life circumstances with non contact scanning devices like the Sarin/OGI/Helium it actually makes sense. Here is why I say this.

...... I can point to specific examples wherein I''ve found labs in error however the degree of rounding GIA has incorporated is by no means unreasonable. One Sarin may report 34.8 crown angles, one 34.76, one 34.9. Bottom line when you take a diamond with each of these crown angles taken from various scanners and round them up to 35 degrees, quite frankly there is no optical visible difference.

Rhino there is no optical difference between 59% table, 40.4 pavilion 34 crown and 58% table, 40.6 pavilion and 34.5 crown?

Sorry if I was not clear mate. I meant to point out that if all measurements on a diamond is equal and the only differences are those minutae in the crown angles there will be no visible difference.

In the descriptions you''re giving though there would be a difference between a 59/40.4/34 and a 58/40.6/34.5.

Date: 4/20/2006 3:04:13 AM
Author: Garry H (Cut Nut)

We have still not seen your consumer survey Jonathon? You said you made video''s of it - it would be good to show it here on Pricescope

Kind regards,

I have video content on the Princess cut survey I conducted last year of the low/medium/low Bscope stone next to the triple VH when I was demonstrating the inconsistency of the Bscope for AGS Ideal princess cuts in that instance (also caused me to make some changes in our Bscope tutorial). You''ll recall a lash out by the other forum which induced me to seek out such a stone for observation testing by common folk to see if they could see any differences.

The content I took of the most recent survey we forgot to turn the mic on so we didn''t have sound.

I since had to return that GIA Ex Steep/Deep but I still have a few painted stones in the inventory ready for another survey and one or two that will always be here on demand for comparisons as well as an ideal stone yet dug out. I am in the process of having a moderate steep/deep cut like around 35.4/41.2 and another around the 36/41.4 (the utter outskirts of GIA Ex grade) so I can physically see where the line is drawn with regards to face up appearance. I almost know what to expect with regards to the 35/41.2 stone but not quite sure what to expect with the 36/41.4. Gut instinct tell me pooper but I don''t want to make a judgment call until it''s physically in my hands and I am able to see it for myself. I would be happy to video any observation testing we make including the stones themselves. In fact I plan on it.

Kind regards,

Great stuff Jonathon.
Looking forward to it.

Please be sure to use some nornal lighting - under tree with no direct sunlight, in normal office lighting - lights on ceiling, under living room type halogens etc - because these situations are what consumers look at diamonds in - and then we can expect some valid results rather than relying on LED and Fluoro''s 10 inches fromn the diamond.

As far as i am concerned the painted vs non painted stones debate is a mute and personal preference issue and holds little interest for me.

 

[Rhino]

Date: 4/20/2006 10:33:46 AM
Author: togal
Rhino, thank you for the information....

It''s a pleasure to help togal. Thank you for the comments/questions.

 

[Rhino]

HI Xchick,

Thank you for posting the numbers. We recently conducted a survey with a diamond almost identical in proportions to yours and compared it to a diamond with an HCA of 1.0 except the current AGS Ideal had painted girdle facets. In the 30 people we showed the comparison to around 95% chose the stone with your proportions. If memory serves me right the stone had an HCA score of 3.6, similar to yours. Here is a link to that thread. I think you will find it interesting since my subject diamond was so close to yours.

https://www.pricescope.com/community/threads/gia-ex-the-consumers-perspective-and-the-technologies.41629/

I can telll you from experience with such a stone that what you have is just fine. Your eyes confirm it as well and that''s what counts most.

Kind regards,

 

[Rhino]

Date: 4/20/2006 1:52:10 PM
Author: aljdewey

Date: 4/19/2006 11:38:30 AM
Author: Virginia

Dear Elizabeth,

Thank you for your inquiry concerning GIA Laboratory Diamond Grading Report # 14850411. Your email was forwarded to me for response.

I have reviewed our records and the “Excellent” Cut Grade shown on this report is incorrect. The error was the result of an incorrect calculation due to a programming issue when the report was re-issued. The error has since been corrected and the “Very Good” cut grade shown on GIA’s Report Check is the correct grade.

Well, I honestly find this reply from GIA very disturbing.

Does it mean she should love the stone any less? Of course not....that''s ridiculous. It still looks exactly the same as it did when she bought it.

EDITED TO CLARIFY:

HOWEVER, it does raise two issues that Virginia has satisfied but many other unsuspecting consumers may not:

1) Stones with an ''excellent'' grade come with a premium. In Virginia''s case, she was very fortunate that she knew enough to bring this back to her vendor, and that her vendor was willing to make a price adjustment based on her fact-finding. What about all the other buyers of GIA stones who won''t know better? and what if they purchase those stones from vendors who aren''t as focused on doing the right thing?

2) Even though Virginia doesn''t ever anticipate selling her stone, what would happen if she did wish to? It''s potentially not as marketable as it was when it was an ''excellent'' stone. While I agree with ''buy the stone, not the paper'', there are those people who want ''mind-perfection''...no different from ''mind-clean''. Those folks would bypass a VG stone, thus shrinking the potential pool of buyers.

While the very sincere apology from GIA is nice, it doesn''t make people whole. That''s really a concern.

Good points Alj. There''s no excuse for mistakes. Emphasizes the need for appraisers and/or vendors who are familiar with what does and does not consitute the GIA Ex grades (or other labs for that matter as all are succeptible to mistakes) so when a lab does make a goof there is someone who can detect it.

Thanks,

 

[Rhino]

Date: 4/20/2006 7:34:06 PM
Author: Garry H (Cut Nut)

Date: 4/20/2006 6:45:58 PM
Author: Rhino

Date: 4/20/2006 3:04:13 AM
Author: Garry H (Cut Nut)

Date: 4/19/2006 8:56:42 PM
Author: Rhino


At first when I saw what GIA was doingwith the rounding I was concerned as well. I am a stickler for detail and to me, the more exacting the better. Once I began to communicate with the research gemologists at GIA I understood their reasoning for the rounding and when I considered real life circumstances with non contact scanning devices like the Sarin/OGI/Helium it actually makes sense. Here is why I say this.

...... I can point to specific examples wherein I''ve found labs in error however the degree of rounding GIA has incorporated is by no means unreasonable. One Sarin may report 34.8 crown angles, one 34.76, one 34.9. Bottom line when you take a diamond with each of these crown angles taken from various scanners and round them up to 35 degrees, quite frankly there is no optical visible difference.

Rhino there is no optical difference between 59% table, 40.4 pavilion 34 crown and 58% table, 40.6 pavilion and 34.5 crown?

Sorry if I was not clear mate. I meant to point out that if all measurements on a diamond is equal and the only differences are those minutae in the crown angles there will be no visible difference.

In the descriptions you''re giving though there would be a difference between a 59/40.4/34 and a 58/40.6/34.5.

Date: 4/20/2006 3:04:13 AM
Author: Garry H (Cut Nut)

We have still not seen your consumer survey Jonathon? You said you made video''s of it - it would be good to show it here on Pricescope

Kind regards,

I have video content on the Princess cut survey I conducted last year of the low/medium/low Bscope stone next to the triple VH when I was demonstrating the inconsistency of the Bscope for AGS Ideal princess cuts in that instance (also caused me to make some changes in our Bscope tutorial). You''ll recall a lash out by the other forum which induced me to seek out such a stone for observation testing by common folk to see if they could see any differences.

The content I took of the most recent survey we forgot to turn the mic on so we didn''t have sound.

I since had to return that GIA Ex Steep/Deep but I still have a few painted stones in the inventory ready for another survey and one or two that will always be here on demand for comparisons as well as an ideal stone yet dug out. I am in the process of having a moderate steep/deep cut like around 35.4/41.2 and another around the 36/41.4 (the utter outskirts of GIA Ex grade) so I can physically see where the line is drawn with regards to face up appearance. I almost know what to expect with regards to the 35/41.2 stone but not quite sure what to expect with the 36/41.4. Gut instinct tell me pooper but I don''t want to make a judgment call until it''s physically in my hands and I am able to see it for myself. I would be happy to video any observation testing we make including the stones themselves. In fact I plan on it.

Kind regards,

Great stuff Jonathon.
Looking forward to it.

Please be sure to use some nornal lighting - under tree with no direct sunlight, in normal office lighting - lights on ceiling, under living room type halogens etc - because these situations are what consumers look at diamonds in - and then we can expect some valid results rather than relying on LED and Fluoro''s 10 inches fromn the diamond.

As far as i am concerned the painted vs non painted stones debate is a mute and personal preference issue and holds little interest for me.

I know that mate.

I think you will be interested in the current video content I am editing Garry. It is specifically on the subject of diamond appearance in many environments and determining which ones show different results than others. One of them includes the common environment that most dealers look under ... desklamp fluoro lighting with a white paper backdrop. Then I show the difference when you add a neautral colored backdrop and how it alters the appearance of steep/deeps amongst other viewing environments both indoor and outdoor.

Peace,
Jonathan

 

[XChick03]

Date: 4/20/2006 9:15:48 PM
Author: Rhino
HI Xchick,


Thank you for posting the numbers. We recently conducted a survey with a diamond almost identical in proportions to yours and compared it to a diamond with an HCA of 1.0 except the current AGS Ideal had painted girdle facets. In the 30 people we showed the comparison to around 95% chose the stone with your proportions. If memory serves me right the stone had an HCA score of 3.6, similar to yours. Here is a link to that thread. I think you will find it interesting since my subject diamond was so close to yours.


https://www.pricescope.com/community/threads/gia-ex-the-consumers-perspective-and-the-technologies.41629/


I can telll you from experience with such a stone that what you have is just fine. Your eyes confirm it as well and that''s what counts most.

Kind regards,

Thank you, Rhino. I''m still reading through the other thread, but it is quite interesting. I know its silly, but the "very good" on the HCA was bothering me.

 

[Rhino]

Date: 4/20/2006 9:32:47 PM
Author: XChick03

Date: 4/20/2006 9:15:48 PM
Author: Rhino
HI Xchick,


Thank you for posting the numbers. We recently conducted a survey with a diamond almost identical in proportions to yours and compared it to a diamond with an HCA of 1.0 except the current AGS Ideal had painted girdle facets. In the 30 people we showed the comparison to around 95% chose the stone with your proportions. If memory serves me right the stone had an HCA score of 3.6, similar to yours. Here is a link to that thread. I think you will find it interesting since my subject diamond was so close to yours.


https://www.pricescope.com/community/threads/gia-ex-the-consumers-perspective-and-the-technologies.41629/


I can telll you from experience with such a stone that what you have is just fine. Your eyes confirm it as well and that''s what counts most.

Kind regards,

Thank you, Rhino. I''m still reading through the other thread, but it is quite interesting. I know its silly, but the ''very good'' on the HCA was bothering me.

Don''t let it. Your only concerns are as Leo stated. If you''re mounting such a stone in a bezel mounting or you continually find yourself in rooms with dark walls on the sides and bright on top then you should have concern. Otherwise if you''re mounting it in prongs allowing a fair amount of backlighting to the stone you should be just fine.

Kind regards,

 

[XChick03]

Thanks again.

I forgot to ask before, is it really an AGS0 or are the angles off like Belle said?

 

[aljdewey]

Date: 4/20/2006 9:25:27 PM
Author: Rhino

Good points Alj. There's no excuse for mistakes. Emphasizes the need for appraisers and/or vendors who are familiar with what does and does not consitute the GIA Ex grades (or other labs for that matter as all are succeptible to mistakes) so when a lab does make a goof there is someone who can detect it.

Thanks,

I guess I'm wondering how it would be possible for appraisers/vendors to know exactly what does and doesn't constitute GIA EX grades if the GIA themselves don't know.

That's not to say they don't know what their grading system is; don't misunderstand. What I'm saying is, if the software that GIA was using had a problem (they said it was a calculation error in the programming), I'd assume that all the vendors' software would also have the same problem if supplied by GIA, right?

As such, how would the vendor/appraiser identify a mistake in the grading report?

Your suggestion is a good one, but that not withstanding.....it still doesn't resolve the fact that the GIA's mistake is likely to cost some group of consumers real dollars out of their pockets. Personally, I feel that more is in order to rectify that GIA mistake than an apology. Unless they make those folks whole, an apology is just lip service.

 

[Mara]

xchick i think under the new AGS0 your stone no longer qualifies...but it doesn't mean your stone ain't pretty, gal!!

as garry said it could be the painted girdle on my new stone (painted-ish is more like it) that is downgrading my stone from a GIA EX to a VG but i don't really care...esp knowing how wackadoodle GIA is being in general about things like painted girdles or rounding numbers (which i still don't think is the way to go). pretty is pretty!!!

 

[Rod]

Date: 4/21/2006 11:48:23 AM
Author: Mara
xchick i think under the new AGS0 your stone no longer qualifies...but it doesn''t mean your stone ain''t pretty, gal!!

as garry said it could be the painted girdle on my new stone (painted-ish is more like it) that is downgrading my stone from a GIA EX to a VG but i don''t really care...esp knowing how wackadoodle GIA is being in general about things like painted girdles or rounding numbers (which i still don''t think is the way to go). pretty is pretty!!!

My thoughts exactly Mara. As the proud owner of a GIA VG stone, pretty is certainly pretty!!

 

[XChick03]

I just think its odd that it was just certified in January but the numbers don''t add up. So I guess it was misgraded?

 

[Garry H (Cut Nut)]

Date: 4/21/2006 11:32:56 AM
Author: aljdewey

Date: 4/20/2006 9:25:27 PM
Author: Rhino

Good points Alj. There''s no excuse for mistakes. Emphasizes the need for appraisers and/or vendors who are familiar with what does and does not consitute the GIA Ex grades (or other labs for that matter as all are succeptible to mistakes) so when a lab does make a goof there is someone who can detect it.

Thanks,

That''s not to say they don''t know what their grading system is; don''t misunderstand. What I''m saying is, if the software that GIA was using had a problem (they said it was a calculation error in the programming), I''d assume that all the vendors'' software would also have the same problem if supplied by GIA, right?

As such, how would the vendor/appraiser identify a mistake in the grading report?

Good point Al, but we have heard about examples (and discussed a couple here) where manufacturers used the Sarin GIA Facetware software to plan diamonds that scanned as excellent but got lower grades.
After GIA laser inscribed the stones the cutters are stuck with a dog that looses them money.

So it is not only a problem for consumers.

 

[Serg]

Date: 4/18/2006 10:27:55 PM
Author: Capitol Bill
It almost goes without saying (again) that I''m disappointed with GIA''s liberal use of rounding and the resulting cut grade system that is far inferior to what GIA is capable of (and has plenty of resources to do right). But flawed as it may be, we have to work with what has been handed down from on high, and we should expect that some glitches would appear (as mentioned in this thread). I''m sure GIA will soon address these early bugs, and I hold out hope that perhaps GIA will recognize the more serious weaknesses in its system and make necessary corrections in the coming months and years.

Now onto the reason for my post -- recently I''ve been encountering a somewhat different phenomenon with stones accompanied by the new GIA reports -- liberal grading of Polish & Symmetry. Specifically, I''ve been seeing GIA Ex/Ex''s that have ''meet points'' all over the place and facet finishes that aren''t exactly what I''ve come to expect as meeting GIA''s ''Excellent'' standard. I''ve mentioned this in passing to a couple of other industry folks and they confirm that they''ve encountered some of the same things. I would love to hear from other vendors if they''ve noticed this. The first time it happened I chalked it up to a ''lucky cert.'' But I''ve been seeing enough of these lately for this to be more than just an isolated anomaly. Perhaps tomorrow if I have the time, I''ll post a recent example with photos. By the way, this is not some veiled attempt at GIA-bashing (heaven knows there''s been more than enough of that to go around lately). I simply think this is an issue worth raising and I''m prepared to present evidence to support my claim.

Respectfully,
Bill Scherlag

Hi, Bill

Did you see liberal of polish grade on small diamonds( 0.3-0.5 ct) ?

I heard about liberal grading of color and clarity grade for small diamonds in last time too. I did not see examples

 

[Capitol Bill]

Date: 4/22/2006 8:20:56 AM
Author: Serg

Date: 4/18/2006 10:27:55 PM

Author: Capitol Bill

It almost goes without saying (again) that I''m disappointed with GIA''s liberal use of rounding and the resulting cut grade system that is far inferior to what GIA is capable of (and has plenty of resources to do right). But flawed as it may be, we have to work with what has been handed down from on high, and we should expect that some glitches would appear (as mentioned in this thread). I''m sure GIA will soon address these early bugs, and I hold out hope that perhaps GIA will recognize the more serious weaknesses in its system and make necessary corrections in the coming months and years.


Now onto the reason for my post -- recently I''ve been encountering a somewhat different phenomenon with stones accompanied by the new GIA reports -- liberal grading of Polish & Symmetry. Specifically, I''ve been seeing GIA Ex/Ex''s that have ''meet points'' all over the place and facet finishes that aren''t exactly what I''ve come to expect as meeting GIA''s ''Excellent'' standard. I''ve mentioned this in passing to a couple of other industry folks and they confirm that they''ve encountered some of the same things. I would love to hear from other vendors if they''ve noticed this. The first time it happened I chalked it up to a ''lucky cert.'' But I''ve been seeing enough of these lately for this to be more than just an isolated anomaly. Perhaps tomorrow if I have the time, I''ll post a recent example with photos. By the way, this is not some veiled attempt at GIA-bashing (heaven knows there''s been more than enough of that to go around lately). I simply think this is an issue worth raising and I''m prepared to present evidence to support my claim.


Respectfully,

Bill Scherlag

Hi, Bill


Did you see liberal of polish grade on small diamonds( 0.3-0.5 ct) ?


I heard about liberal grading of color and clarity grade for small diamonds in last time too. I did not see examples

Sergey,
Thanks for picking up this topic. I figured that others simply weren''t interested in discussing this further. To answer your question: I haven''t noticed the liberal grading of Polish & Symmetry on small diamonds because I typically don''t handle a lot of GIA-graded goods in the 0.3 - 0.5ct range. Rather I''ve noticed this with stones in the 1ct+ and 2ct+ ranges. I actually have some photomicrographs of a recent 2ct+ stone and I''ll post them in a new thread at the beginning of this coming week (Mon or Tues).

Thanks again for your interest.

Regards,
Bill Scherlag

 

[Rhino]

Hi XChick,

Please forgive my delayed response here as I got called away over the past few days on more pressing matters.

Date: 4/21/2006 10:42:06 AM
Author: XChick03
Thanks again.

I forgot to ask before, is it really an AGS0 or are the angles off like Belle said?

The answer to this was yes but I think you already knew.

As you saw in the other thread I linked you to, your type of stone was actually preferred by more consumers when comparing next to certain AGS ideal types.

Kind regards,
Jonathan

 

[Rhino]

Please forgive my delay Alj.

Date: 4/21/2006 11:32:56 AM
Author: aljdewey

Date: 4/20/2006 9:25:27 PM
Author: Rhino

Good points Alj. There''s no excuse for mistakes. Emphasizes the need for appraisers and/or vendors who are familiar with what does and does not consitute the GIA Ex grades (or other labs for that matter as all are succeptible to mistakes) so when a lab does make a goof there is someone who can detect it.

Thanks,

I guess I''m wondering how it would be possible for appraisers/vendors to know exactly what does and doesn''t constitute GIA EX grades if the GIA themselves don''t know.

That''s not to say they don''t know what their grading system is; don''t misunderstand. What I''m saying is, if the software that GIA was using had a problem (they said it was a calculation error in the programming), I''d assume that all the vendors'' software would also have the same problem if supplied by GIA, right?

As such, how would the vendor/appraiser identify a mistake in the grading report?

Excellent questions.

Here''s the thing ... the software does contain their proper algorythms. Of course there are additional elements to look for beyond what the software tells you (digging, painting, proper girdle thickness at both the valley''s and bezels, culet, polish & symmetry). For example if we run a diamond on our Sarin DiaMension and came up with the proportions that were listed on these folks reports our software would have picked up the error immediately. One does not necessarily need the plugin software to determine the grade by the proportions though as there are actually 3 different ways one can confirm if the information is right. There is

a. the Sarin plug in software.
b. the FacetWare software in their site
c. There are lookup tables they have published both online and also in their new Diamond Grading Lab Manual.

I''ve looked over each of these and while they have had problems with their internal software, if one consults these other methods they all say the same thing. I had recently found a mistake on a diamond we recieved back which received an "excellent" grade but I personally knew the stone was dug out and should not have received the top grade. Everythign else on it was ideal however the digging just crossed the threshold and impacted the face up appearance of the stone. I notified GIA about it and we will be getting the corrected report.

All the other stones we had submitted were just fine. I think they may be going through a bit of a growing pain with the new system but thankfully it has not been on the majority of stones I''ve seen. As usual, we would offer the same counsel to any consumer as before the new grading system was instituted and that''s to have a professional check out the stone to confirm it is indeed what the consumer is paying for. With the new grading systems offered by both labs it is wise for any consumer to get that peace of mind before plunking down the $$$.

Your suggestion is a good one, but that not withstanding.....it still doesn''t resolve the fact that the GIA''s mistake is likely to cost some group of consumers real dollars out of their pockets. Personally, I feel that more is in order to rectify that GIA mistake than an apology. Unless they make those folks whole, an apology is just lip service.

I can''t speak for GIA but I do understand where you''re coming from Alj. I would hate to be the one who, if a consumer wanted to sell a diamond and had a report with a mistake on it, to be the one to break the news that the stone really wasn''t an Ex. From what I am told they''re already taking care of the situation.

Kind regards,

 

[XChick03]

Date: 4/23/2006 1:08:59 PM
Author: Rhino
Hi XChick,


Please forgive my delayed response here as I got called away over the past few days on more pressing matters.

Date: 4/21/2006 10:42:06 AM

Author: XChick03

Thanks again.

I forgot to ask before, is it really an AGS0 or are the angles off like Belle said?

The answer to this was yes but I think you already knew.

As you saw in the other thread I linked you to, your type of stone was actually preferred by more consumers when comparing next to certain AGS ideal types.


Kind regards,

Jonathan

Thank you again.

I (stupidly) mentioned this to my fiance, and he''s kind of ticked now. Mostly because we paid for an ideal cut and didn''t get one and he says he wanted me to have the best. Also, we''ve been looking at it a lot more closely now and he''s starting to notice things about it that have always bothered me. When I first got it, it wasn''t as sparkly as I expected but I was thrilled and thought it was gorgeous anyway. Now everytime I look at it in direct light, it looks really dark around the center. I don''t if it''s all in my head or what, but I don''t think there''s much we can do since we are well past the 30 day return period.

 

[Rhino]

Hi Xchick,

Actually in direct lighting most ideal cuts take on a darker body appearance overall. The positive is that the flashes of light will be brighter, more intense and at a greater frequency. I have just finished shooting detailed footage of this phenomena in an upcoming program we''ll be featuring.

One reason why myself, Garry and many other gemologist/jewelers dislike certain direct lighting (which also includes many led environments) is that they give steep/deep (not like yours though, but the bad ones) a lighter overall body appearance which is only seen in limited viewing enviroments and can mislead the unsuspecting diamond buyer who is viewing it in typical jewelry store spot lighting. Once the lighter body colored steep/deep is brought into normal day lighting environments and observed on neutral colored background, the decrease in brightness becomes apparent which is why we see threads from time to time ... "My diamond doesn''t look so bright out of the jewelry store" ... or along those lines. In most jewelry stores there is typically spot lighting which is not common to everyday viewing environments.

One primary reason I like the new DiamondDock is because it shows the stone in lighting that people find themselves in often and can be used on the jewelry store showroom.

While I haven''t personally seen your stone the specs on it sounded good. If the place you purchased from offers a tradeup policy you may want to consider viewing it side by side to other stones within specs you feel you''d be more comfortable with and see if you can really see any differences that you either prefer or don''t prefer. You may do so only to find out you really do prefer yours most.

Kind regards,
Jonathan

 

[Garry H (Cut Nut)]

Date: 4/23/2006 8:18:35 PM
Author: Rhino

One reason why myself, Garry and many other gemologist/jewelers dislike certain direct lighting (which also includes many led environments) is that they give steep/deep (not like yours though, but the bad ones) a lighter overall body appearance which is only seen in limited viewing enviroments and can mislead the unsuspecting diamond buyer who is viewing it in typical jewelry store spot lighting.

Kind regards,
Jonathan

I did not say that Rhino?

 

[Rhino]

Date: 4/23/2006 8:27:12 PM
Author: Garry H (Cut Nut)

Date: 4/23/2006 8:18:35 PM
Author: Rhino

One reason why myself, Garry and many other gemologist/jewelers dislike certain direct lighting (which also includes many led environments) is that they give steep/deep (not like yours though, but the bad ones) a lighter overall body appearance which is only seen in limited viewing enviroments and can mislead the unsuspecting diamond buyer who is viewing it in typical jewelry store spot lighting.

Kind regards,
Jonathan

I did not say that Rhino?

My bad. Other Gmen I have spoken to on this subject agreed and I thought I recalled us talking about this before. If not, my apologies. Curious to hear your thoughts if we haven''t.

Peace,

 

[Rhino]

Here is a photograph of the phenomena I''m talking about. This shot is taken in typical jewelry store lighting. When diamonds are shown in tweezers or against a light backdrop in these environments it can make poop stones appear to be *brighter*. Once you bring that diamond into normal daylight conditions the truth is revealed however. When I took this picture I purposely sought minimal bright reflections in the Ideal so as to capture body appearance between the 2 stones.

Peace,

 

[Rhino]

Not my best picture of these 2 stones but here are both under diffuse daylight in the DD. Look how different the appearance is now between the 2 and the crapper is revealed exactly for what it is.

Edited to add: the stones are transversed in each of the pix I posted. The poop stone in the first pic is the one on the left, in this post it is the stone on the right.

Regards,

 

[Garry H (Cut Nut)]

Direct light, and too much intense light makes diamonds look dark. Our eyes then have difficulty resolving the bright parts from the not so bright parts and leakage = the same as other parts that are not bright.

It is a fundemental part of what Sergey was describing in this thread https://www.pricescope.com/community/threads/how-lighting-can-influence-on-grade-appearance.38583/=

In these TWO photo''s the top one is taken with just the ambient room light -the bottom one is in a similar color grading environemnt - a bit like Diamond Dock.

The stones are DARKER not lighter in the intense light.


It is a very important concept that took me a while to bring together Jonathon.

It is why we have so many consumers asking about why their diamonds look dark in direct sunlight.

You have debated this with me for a while now - i think it is time you picked up on what is being said - the fact that you assumed that I agreed with you shows you have not been reading / listening Jonathon.

 

[Rhino]

Thanks for posting that. I recall seeing that graphic before. My apologies for not being able to read all your content & posts as I don't find the time to come here nearly as often as I'd like. It appears we're on the same page regarding the issue of strong light causing a darker body appearance. I would not have used such dark color stones for an illustration as the colors in your graphic but either colorless or near colorless since that is what most people purchase but the point is made nonetheless.

It should be pointed out however that in many (not all) direct light environments finely cut diamonds do take on a darker body appearance yet the flashes of light within the diamond are stronger/more intense and at a greater frequency. At least this has been my assessment.

For the record, the graphic you did post does not represent what DD does to the appearance of diamonds in observing under their daylight viewing. Far from it. Check out the images I just posted.

Peace,

 

[XChick03]

That might be what I am seeing then. It looks a lot like the ones Garry posted. Though, sometimes it still appears to be a dark gray color around the center even when its not in direct lighting. For example, we were in my car the other day and my fiance noticed the darkness in the center for the first time and it was cloudy that day.

I think it just doesn''t perform as well as I had hoped. A friend of mine has a Leo diamond, about the same size as mine, and I kind of expected my diamond to sparkle and have as much fire as that one, but it doesn''t. I think I just expected too much. I''ve also compared several pictures of ideal cuts and some not-so-ideals and mine seems to look more like the latter, even in the second picture you posted, it looks more like the poorly cut one. But I know I can''t really depend on pictures.

Sorry if I''m rambling now, this whole thing just bothers me. I feel bad that I don''t really love this stone like I did at first. Maybe I just have a case of buyer''s remorse. It''s just like after the excitement of getting it and being engaged wore off, I started noticing bad things about it, like that there''s a dead spot on one side. Then I played around with the HCA and realized it wasn''t ideal after all and that maybe it wasn''t all in my head. My fiance kind of wants to just get a new diamond now, he called the place we bought it from today, to see if they''d possibly give us a refund because of the circumstances, but they haven''t returned his call. So, I guess we''ll just have to wait and see what happens.

Thanks again, Jonathan. You''ve been very kind and if we do decide to get another stone, GOG is the first place we''re looking. Just like everyone told me to in the first place.

 

[Garry H (Cut Nut)]

Date: 4/24/2006 12:16:20 AM
Author: XChick03
That might be what I am seeing then. It looks a lot like the ones Garry posted. Though, sometimes it still appears to be a dark gray color around the center even when its not in direct lighting. For example, we were in my car the other day and my fiance noticed the darkness in the center for the first time and it was cloudy that day.

I think it just doesn''t perform as well as I had hoped. A friend of mine has a Leo diamond, about the same size as mine, and I kind of expected my diamond to sparkle and have as much fire as that one, but it doesn''t. I think I just expected too much. I''ve also compared several pictures of ideal cuts and some not-so-ideals and mine seems to look more like the latter, even in the second picture you posted, it looks more like the poorly cut one. But I know I can''t really depend on pictures.

Sorry if I''m rambling now, this whole thing just bothers me. I feel bad that I don''t really love this stone like I did at first. Maybe I just have a case of buyer''s remorse. It''s just like after the excitement of getting it and being engaged wore off, I started noticing bad things about it, like that there''s a dead spot on one side. Then I played around with the HCA and realized it wasn''t ideal after all and that maybe it wasn''t all in my head. My fiance kind of wants to just get a new diamond now, he called the place we bought it from today, to see if they''d possibly give us a refund because of the circumstances, but they haven''t returned his call. So, I guess we''ll just have to wait and see what happens.

Thanks again, Jonathan. You''ve been very kind and if we do decide to get another stone, GOG is the first place we''re looking. Just like everyone told me to in the first place.

This is the third page of an article discussing the issue of leakage just inside the table of gIA Excellent diamonds. http://journal.pricescope.com/Articles/37/3/GIA-Excellent-Cut-Grade-Case-Study.aspx
Are you seeing the dark zone in the image on the lower right?

These are the AGS 0 proportions you posted XChick
It''s new, dated January 10, 2006.
Depth: 61.6
Table: 56.5
Crown angle: 34.9
Pavilion angle: 41.2

What we dont know is if it is a New format (with light performance grading) or Old Format (with old proportion grading) - a scan would help us sort that out - or tell us if it has the words "light performance" meaning it is a new report.

They have been under pressure to keep the old service even though it seems to run counter to their "ideals" (pun intended).

On AGS''s new system this stone may be AGS 1 to AGS 4

but it would easily qualify for the GIA''s Excellent (but not HCA Ideal).

But as Rhino has said - as long as it is set up a bit - it will gain some light thru the pavilion - and if you read the thread opinned at the top of the page - you can understand more about all this stuff

 

[XChick03]

Yes, that''s exactly what I''m seeing. My stone looks a lot like the one on the right, in all three pictures. I even asked my FI without telling him which stone was which and he agreed. And the cert doesn''t have light performance on it.

I''m starting to understand this a lot more now. I just wish I would''ve known all this three months ago.

 

[Rod]

Date: 4/24/2006 12:16:20 AM
Author: XChick03
That might be what I am seeing then. It looks a lot like the ones Garry posted. Though, sometimes it still appears to be a dark gray color around the center even when its not in direct lighting. For example, we were in my car the other day and my fiance noticed the darkness in the center for the first time and it was cloudy that day.

I think it just doesn''t perform as well as I had hoped. A friend of mine has a Leo diamond, about the same size as mine, and I kind of expected my diamond to sparkle and have as much fire as that one, but it doesn''t. I think I just expected too much. I''ve also compared several pictures of ideal cuts and some not-so-ideals and mine seems to look more like the latter, even in the second picture you posted, it looks more like the poorly cut one. But I know I can''t really depend on pictures.

Sorry if I''m rambling now, this whole thing just bothers me. I feel bad that I don''t really love this stone like I did at first. Maybe I just have a case of buyer''s remorse. It''s just like after the excitement of getting it and being engaged wore off, I started noticing bad things about it, like that there''s a dead spot on one side. Then I played around with the HCA and realized it wasn''t ideal after all and that maybe it wasn''t all in my head. My fiance kind of wants to just get a new diamond now, he called the place we bought it from today, to see if they''d possibly give us a refund because of the circumstances, but they haven''t returned his call. So, I guess we''ll just have to wait and see what happens.

Thanks again, Jonathan. You''ve been very kind and if we do decide to get another stone, GOG is the first place we''re looking. Just like everyone told me to in the first place.

XChick.......I''m not trying to make light of your situation. I think we all analyze our stones to death. I''m betting your stone is stunning in person. I too have found that my stone (whcih is only GIA Very Good) looks great in some lighting situations and in others, not as great. Overall though, my stone is beautiful and as her temporary custodian, is very special to me.

Here''s the light part

You my friend, may be DOCD afflicted. In case you haven''t seen this in any of my threads, it is here for your amusement.............

You have Diamond Obsessive Compulsive Disorder (DOCD), an illness many of us suffer from on this forum. DOCD, discovered by Dr. Brillianteering in the early 1900''s, is a manifestation of mental anomolies when perfectly sane individuals become the owners of high quality diamonds. What typically occurs for an accurate DOCD diagnosis is euphoria upon the purchase of a nice gem, followed by self doubt, and ultimately downright concern that the purchased stone has somehow magically changed in appearance while the owner slept.

While there are no known medications available to combat DOCD, many people have reported the symptoms are reduced or completely eliminated by visiting chain jewelry stores, such as Zales or Kay, or having lunch with a friend who has a stone of poorer quality than the DOCD sufferer.

 

[strmrdr]

Date: 4/24/2006 9:46:57 AM
Author: Rod

Date: 4/24/2006 12:16:20 AM

You have Diamond Obsessive Compulsive Disorder (DOCD), an illness many of us suffer from on this forum. DOCD, discovered by Dr. Brillianteering in the early 1900's, is a manifestation of mental anomolies when perfectly sane individuals become the owners of high quality diamonds. What typically occurs for an accurate DOCD diagnosis is euphoria upon the purchase of a nice gem, followed by self doubt, and ultimately downright concern that the purchased stone has somehow magically changed in appearance while the owner slept.

While there are no known medications available to combat DOCD, many people have reported the symptoms are reduced or completely eliminated by visiting chain jewelry stores, such as Zales or Kay, or having lunch with a friend who has a stone of poorer quality than the DOCD sufferer.

Yikes now its got a name!
My name is storm and I have DOCD therefore I must visit every jewelery store within 20 miles. Twice! :}
We reject diamonds around here that are better in most lighting conditions than 99.9% of all diamonds out there so its easy to lose track of just how bad most diamonds are.
I do have to temper that but saying, having looked at a few diamonds under the IS and handheld aset there are some shockingly well cut diamonds in the wierdest places.
The other day I was looking at an I2 diamond with 3 feet visible inclusions that had perfect arrows and great light return.
3/4ctw earrings for $700 --- edit it was the 1ctw that was $1000
*shrug*