Why would anyone object to painting?

[Rhino]

Date: 5/26/2006 8:27:43 AM
Author: JohnQuixote

Should an identical diamond with only 5 deg be ''dinged?'' One with 4 deg? What about other configurations? There are many variables.

It is why I have repeatedly said there''s no way one painted diamond can represent all.


Oops... forgot to address this. John, your totally right ... no one painted diamond can represent it all. GIA is not saying that.

However, the question stands ... at what degree is it visible to the human eyes? GIA has attempted to answer this question with the chart I had posted previously on this thread. Our personal experience thus far is that we have been able to see the difference amongst the GIA VG''s that we''ve had here that were dinged for reasons of painting.

Admittedly the only difference I saw in the painted stone that got the GIA Good and the AGS 1 for painting, I was not able to see any notable difference in the face up appearance between that and the VG''s I''ve seen but only in the anlaysis of the girdle itself.

The question of 4 deg, 5 deg, etc. My approach to this subject is really quite simple. Firstly I am still a believer in "innocent until proven guilty". I don''t believe GIA is conspiring against any individual or company. If at this point in time GIA is saying 5 degrees gets dinged, then I say ... lets see it and see if we can see any deviation in appearance causing more darkness than brightness. If not then we have discovered a potential flaw in the system. If so, the system stands justified. btw here''s the model of hte actual painted stone we used in our most recent survey of the painted vs the GIA Ex steep/deep. I can''t recall the degree of painting on this one inparticular but Serg stated what it was in a prior thread.

Peace,

 

[JohnQuixote]

Date: 5/26/2006 9:45:09 AM
Author: strmrdr

Date: 5/26/2006 8:38:06 AM
Author: JohnQuixote

All things considered:

It strikes me as bizarre that so much exaggeration is happening lately regarding these minute painting differences when diamonds within GIA EX take on vastly different appearances for more glaring reasons.

There are 4 or 16 things well ahead of painting that are more important to how a diamond performs than painting.. I think we agreed that's very true.
But its also equally true across a wide variety of lighting conditions it has a noticeable effect on the diamonds personality which can make someone prefer one style over the other.

The things I feel have a greater effect by far are:
1-10 are lighting lighting lighting
11: pavilion angle
12: crown angle and its relationship to the pavilion angle.
13: optical symmetry
14: LGF%
15: type of setting open or bezel, one thing that the discussion of the GIA grading system has shown me is that the type of setting can be a huge consideration once you get outside the traditional super-ideal range.
16 then finaly girdle treatment.

Great priorities.

Your first 10 also have the most influence on the remaining 6.

Painting is appropriate in the last position because when #11, #12, #13 and #14 are in place it is a simple matter of taste, even if noticable. We really are making mountains out of molehills here (uh oh...that involves digging).

 

[Rhino]

Date: 5/26/2006 8:30:33 AM
Author: JohnQuixote

Optical properties of one configuration can''t be stereotyped for another.

This is the flaw with GIA''s stereotyping approach: Overall configuration and optical symmetry change the playing field: Diamonds cut near Tolkowsky proportions with good OS can perform their best even when painted to a large degree, whereas those with less optimum proportions and poor OS cannot take even moderate painting before the look changes.

There are too many variables to try and stereotype all diamonds as needing to conform to one set of parameters.

(hypothetical numbers)

John ... haven''t you read anything I''ve posted? I''ve stated this I don''t know how many times in this thread already and in other threads. GIA is not mass grading all painting. Far from stereotyping they''ve broken it down to varying degrees. I can show you examples of painting that do not get dinged in their system (and rightfully so) and ones that do which we''ve been able to visually confirm and these have been diamonds with precision optical symmetry.

Regarding this statement: "Overall configuration and optical symmetry change the playing field: Diamonds cut near Tolkowsky proportions with good OS can perform their best even when painted to a large degree..."

My question would be how many painted girdle diamonds have you compared side by side that meet the GIA VG or G grade that have common optical symmetry and ideal optical symmetry that cause you to make such a statement? Could you provide us with an example(s)? A photograph of the 2 in diffuse daylight would be sufficient to make the comparison and see the greater amount of darkness in the ideal with common OS. I am finding that OS does not improve the appearance of painting and digging but perhaps I am wrong. If you could provide a photograph of 2 and the data (Gem files ok) I''d be interested to see what comparisons have led you to that conclusion because both GIA and AGS said OS has no bearing on the overall cut grade/appearance.

Kind regards,

 

[Rhino]

Date: 5/26/2006 8:35:20 AM
Author: JohnQuixote


GIA arrived at 3 drawings of painted girdles for EX by which to judge all diamonds.
I think GIA took a shortcut.

LOL ... you''re saying GIA is judging painting by 3 drawings? I''d be interested to hear where you got this from and I''d like to see the drawings that their graders use to judge all painted diamond.

 

[Rhino]

Hey Wink.

Rhino and I already agree to dissagree on the painting thing, but there are a lot of areas about the GIA system that I bet Jon would agree with you and I on. I am still hoping that the system they have come up with will be changed to one that is less politically motivated to keeping the diamond cutters happy and more motivated to rewarding excellence.

I am open minded to listening Wink. I have my criticisms of both systems which I''ve published in our cut tutorial along with high praises for what I like about both systems as well. My apologies if it appears that this subject is getting pounded.

That''s really not my intent and I have no less respect for companies who cut precision products such as 8* and WF. You know I am open and reasonable to new ideas friend. What perhaps annoys me about all of this is if someone (such as myself) has an opinion that differs I''ve been personally attacked because of it and that is just not right. I don''t appreciate having my integrity called into question because I see things differently (particularly from the older thread back in March). Do you understand where I''m coming from on this Wink?

I am happy to discuss other elements of the GIA or AGS system that you may or may not agree with and see if we can find some common ground. Perhaps we can start a thread on digging?

hehe I think we''re all in agreement regarding that subject. Heck even GIA and AGS are! Even down to the thresholds of what gets Ex/Ideal from what I''ve found at least.

Kind regards,

 

[JohnQuixote]

Date: 5/26/2006 3:23:32 PM
Author: Rhino

Date: 5/26/2006 8:35:20 AM
Author: JohnQuixote



GIA arrived at 3 drawings of painted girdles for EX by which to judge all diamonds.
I think GIA took a shortcut.

LOL ... you''re saying GIA is judging painting by 3 drawings? I''d be interested to hear where you got this from and I''d like to see the drawings that their graders use to judge all painted diamond.

Rhino,

From this article: http://lgdl.gia.edu/pdfs/estimating_painitng.pdf

The most direct way to visually assess the level of painting and/or digging out on a round brilliant is to examine the girdle profile of the diamond...Consistent with the five categories in the GIA Diamond Cut Grading System, we have divided into five levels the extent of painting and/or digging out possible on round brilliant diamonds. The illustrations in figures 4 and 5 (a full page version is available at the end of this document) show examples of the approximate extent of painting and digging out allowed for the top four cut grade categories as represented by the girdle profiles.

Figure 4. These girdle profile example iillustrate the extent of painting allowed for each of the top four cut grade categories. A diamond with a girdle profile more irregular than “severe” would not lower the cut grade beyond “fair.”

Here the 3 drawings GIA provided in their full page as painting allowances for EX grade (I added 3 for VG as well).

If there is more please elaborate for me. I''d be glad to hear it!

 

[JohnQuixote]

As a contrast, AGS uses direct ray-tracing of the 3D model for each diamond.

The AGS upper halves indexing study released shows 550+ different configurations for the 0 grade alone.

Excerpt from AGS email (with permission to post):

Gentlemen:

In June of last year we disseminated the attached information to the industry. This .pdf file shows how much a cutter can ‘paint’ or ‘dig’ the upper halves and still expect to get AGS 0 light performance for a round brilliant with 50% star length and 80% lower girdle height.

I have been reading the posts on Pricescope about ‘Problems with Diamond Dock’. One of the posts from michaelgem says “Both organizations recommend against painting”. From my perspective, this generalized statement is misleading. We neither endorse nor oppose ‘painting’ or ‘digging’. We ray trace 3D models of diamonds. If the stone gets the values for brightness, contrast, dispersion and leakage - it gets the grade.
The judgment is made based on 3D modeling in a diamond-specific ray tracing engine. If the painting or digging is negative and performance values are not met it will not receive the 0 Ideal grade.

I have attached a portion of their 18-page PDF. It includes data on 550+ configurations for painting (for AGS0 alone).

 

[Rhino]

Date: 5/26/2006 11:22:55 AM
Author: Wink

Date: 5/26/2006 11:18:33 AM
Author: Rhino
Seriously though Marty, the DD introduces into the jewelry store environment (which is typically strictly a spot lighting environment) an accurate assessment of brightness which the consumer typically doesn''t see when viewing diamonds in a jewelry store atmosphere. That is a HUGE plus IMO.

If only it were true. Rhino, I guess this is just going to be another area in which we have to agree to dissagree. This device simply does not create an accurate assesment of brightness, as is easily and convincingly shown with Gary''s pictures of the good and bad stone side by side both looking pretty good in the DD.

I carry a set of those stones in my pocket with me where ever I go and I have never seen the bad stone look any where near good EXCEPT in the DD.

Wink

Wink ... I can tell you beyond a shadow of a doubt it''ll look like a crapper in the DD as well. I''ve read and studied Garry''s article and have even published a response only to find out that Garry changed certain elements in the article and I''m in the process of revising it to reflect the most current publishing. Drop me an email and I''ll link you. There are grave errors in that article which have obviously led you astray in your conclusions about the DD Wink. Drop me a line and I''ll forward you to what I have published already. I''ve been paying attention to this thread (subscribed so I see the responses in email) but I really need to finish up my response to that so that you hear the perspective of one who has worked with it daily for 5 months instead of just 3 days. Just curious Wink, have you every really viewed your 2 stones in the DD yet? If you don''t mind Wink, I''d love to borrow them from you and photograph them. I''ll foot the shipping of course and show you both SLR photography and high definition video of the subject stones. This will I am sure settle the issue forever in your mind regarding the DD. If I am wrong, the photography will reveal that too and I will stand corrected. I look forward to hearing back from you on this.

Peace,

 

[Rhino]

Date: 5/26/2006 1:23:16 PM
Author: Mara
no rhino i don''t want to guess about dug out stones. i''m talking about painting. they are separate things are they not?

this stuff IS very confusing for the average consumer to understand, DS, but to be honest, most of what is going on here is between the experts of the industry and us consumers just kind of dazzedly sit by taking it all in until maybe someone says a line in english we cana actually understand.

but i love it. that is the beauty of PS for me. trying like hell to figure out all the diagrams and the diamond tech speak is way more interesting than which celebrity got divorced or which bathing suit to buy even though i can subscribe to that kind of stuff too most of the time.

i don''t know if you care about my opinion, DS, but here it is. the painting/non painted discussion for most consumers on here will be a moot point when discussed because they are discussing the tiniest of split hairs amongst exceptional stones. i love my painted stones, i love the classics i''ve seen as long as they are precisely cut to my own requirements, kenny is busy doing his real life study, in reality it all just comes down to preferences. you will NOT be unhappy with a precisely cut classic end-leakage stone and you will NOT be unhappy with a precisely cut slightly painted stone. that''s the bottom line. if you take anything else away from this discussion, realize that these individuals here are discussing the nuances between probably the top 1% of the best cut diamonds in the world. it''s not like a zales stone vs an eightstar. regardless of which you buy, it will be a firecracker to you.

i hope THAT makes sense because newbies should not be confused if they can read and decipher that last paragraph. really no one should. and if they want to delve into the nuances more...then by all means keep reading this thread and others like this. it''s where the real education comes into play.

Well said Mara.

 

[Rhino]

Date: 5/26/2006 2:02:29 PM
Author: adamasgem

Your ''BS'', so to speak, has more to do with your probably taking out of context any statement made to you ( which I have no direct knowledge of) which are contradictory with FACTS.

As to my humor with the KittyDock, you just don''t get it Rhino. The KittyDock envrionment, in my opinion, and I believe others here who are capable of doing the analysis, is inconsistent with GIA''s stated baselines for their ''metrics'', an obscured hemisphere.

It is a SALES tool, base on the fact that RBC diamonds typically have their highest efficiency for ''light return'' from direct overhead lighting. That ''mirror'' (as well as confusing glare) effect will be a function of the look angle.

And you, like GIA, seemingly tried to overly simplify ''painting'', and failed miserably at characterising it. And given your position as a merchant who may not be able to get the type of painted high optical symmetry stones you once promoted and sold, have tried, at least in my opinion, to trash them.

Your customers will purchase from you what you have in your inventory, and probably largely based on the particular ''spin'' EVERY merchant puts on their products, glossing over deficiencies or trying to put everything in the best ''light'', hence the KittyDock.

I doubt that you will tell a customer that the GIA EX you are trying to sell them would get an AGS 3 or 4, or would have been classically called a commercial or promotional make stone 6 months ago.. But that is just my opinion.

You are too comical Marty.

Apparently you are unaware of the facts that ...

a. I have access to precise optically symmetrical diamonds with painted girdle facets and can get them as I need them. I would link you to some but can''t.
b. The stones I primarily feature on our site easily make both AGS and GIA top grades.

Contrary to your false statements about me and my inventory I challenge you to find one diamond on my site that is GIA Ex that would get AGS 3 or 4. If you can''t then keep your rude and false comments to yourself.

You can''t resist making things personal can you Marty?

 

[strmrdr]

This is getting rinkidinkulas
Why doesnt everyone call a sieze fire for the weekend on this subject and think about how to discuss this in a more level headed adult manner and a less confusing one?

 

[strmrdr]

*storm slinks off and crawls back under the bed*

 

[WinkHPD]

Date: 5/26/2006 3:47:43 PM
Author: Rhino

Hey Wink.

..snip.. What perhaps annoys me about all of this is if someone (such as myself) has an opinion that differs I''ve been personally attacked because of it and that is just not right. I don''t appreciate having my integrity called into question because I see things differently (particularly from the older thread back in March). Do you understand where I''m coming from on this Wink?

Rhino,

I am not at all sure where you are coming from. If you are saying that you feel I have personally attacked you, then no, I do not believe that I have. That is not my style or my desire. I sincerely dissagree with you about the painting issue and the diamond dock issue and have stated my dissagreement and will continue to do so.

Both Richard von Sternberg and Brian The Cutter produce an incredible stone that does NOT suffer visually from the painting done in my opinion and in the opinion of the clients and friends that I have shown them to. Some people like the larger broader flashes from the EightStar than the smaller flashes from the H&A cut stones that I have here, and I can readily see the difference between some of the Israeli cut H&A''s that I have here and the EightStars in terms of light, but only because I have a LOT of practice at it. When I put one of Paul''s stones next to a comperable EightStar I have to weigh them to make sure I did not mix them up, even though I THINK I know which is which. Some days I will give a tiny edge to one, and some days I will give a tiny edge to the other. The differnces are very minor, and do not involve darker edges.

Did I mention the word tiny?

I do not like the implication that painted stones are bad. I will fight it tooth and nail every time I see it. It is bad if done incorrectly. It can actually enhance the visual appearance of the stone if done correctly.

I do not believe that Paul does painting on his stones, but that would be a conversation to have with him, as I do not know. His stones pretty much all get AGS 0 cut grades except for a few that have minor polish issues because of the material and get an AGS 1 cut grade for the polish deduction, so if he does do ANY it would be very minor. I state this only so that there be no misunderstandings by anyone that I dissagree with you on this because of Paul''s stones. (By the way, I challenge ANYONE to identify these AGS 1''s using only their eyes, not knowing in advance which stones are 1''s and which are 0''s. I have trouble doing it, in most cases, with a scope.)

I dissagree with you Jon, but I do not feel that I have attacked you personally in any way. I sincerely believe that you are a passionate person and I believe that in these two cases you are passionately wrong. You believe that I am wrong, it does not hurt my feelings and I respect your right to believe the way that you do. If you believe that this is a personal attack on you, then I wish to apologise. It is not intended to be such.

We have dissagreed before, and we have agreed before and I am sure that we will again, although probably not on these two issues. I hope you have a great weekend, I get to meet a dear friend from Pricescope tomorrow, so my weekend will indeed be a treasured one.

Wink

 

[WinkHPD]

Date: 5/26/2006 3:59:29 PM
Author: Rhino
If you don't mind Wink, I'd love to borrow them from you and photograph them. I'll foot the shipping of course and show you both SLR photography and high definition video of the subject stones. This will I am sure settle the issue forever in your mind regarding the DD. If I am wrong, the photography will reveal that too and I will stand corrected. I look forward to hearing back from you on this.


Peace,

Ah, this is more the Jon I know and like. Remind me when I get back from Vegas and I will send you a pair of them. I am already at home today and not planning on going to the office tomorrow and will only be there on Tuesday preparing to go to Vegas, so it is unlikely to happen then.

I will look forward to seeing your pictures.

Wink

 

[Garry H (Cut Nut)]

Date: 5/26/2006 11:24:10 AM
Author: Rhino

Date: 5/25/2006 12:58:01 AM
Author: Garry H (Cut Nut)

Date: 5/24/2006 10:54:50 PM
Author: strmrdr

Date: 5/24/2006 10:32:10 PM
Author: Garry H (Cut Nut)
For all those who have DiamCalc and want to see what a diamond looks like in the cat liter box - here is my best approximation for the lighting in DiamCalc.

way too much head shadow compared to the DD, no cigar

Storm try the attached 46 degree dome lighting that gIA used as their model for obsured lighting.
I modeled it here with fading to the hemisphere light, which i think they would approve of.

Since this was the lighting model they used in their software ''metric'' that approximated the dealer lighting that the fluoro DD light aproximates - check it out and see if you think I have too much head shadow in the DD?

Hi Garry,

The white dome was used in some of the studies but none of the observation testing was performed with this. White dome stuff is kinda moot.

Rhino you claim to be an expert in this area, yet you really do not follow through before making your statements.
Read tha last line here and you will see that about 8% of GIA''s total observations were done thru this dome (5095).
http://www.gia.edu/pdfs/cut_table_1.pdf
http://www.gia.edu/pdfs/cut_table_1.pdf

great work I am sure John, but Wink - forget it - this is a non issue

 

[Rhino]

Hey Wink,

Just ready to head out but caught your reply in email.

I am sorry I did not clarify in my email about the personal attacks. You are the last person on this planet who makes me feel that way bro. Let me say that of all the people in the trade I have come to know via the forums you are one I hold in high esteem. We''ve shared many joys and frustrations both here and in email over the course of time and I just want ya to know I think the world of ya man.

Fo rizzeal.

 

[Rhino]

Date: 5/26/2006 5:21:54 PM
Author: Wink

Date: 5/26/2006 3:59:29 PM
Author: Rhino
If you don''t mind Wink, I''d love to borrow them from you and photograph them. I''ll foot the shipping of course and show you both SLR photography and high definition video of the subject stones. This will I am sure settle the issue forever in your mind regarding the DD. If I am wrong, the photography will reveal that too and I will stand corrected. I look forward to hearing back from you on this.


Peace,

Ah, this is more the Jon I know and like. Remind me when I get back from Vegas and I will send you a pair of them. I am already at home today and not planning on going to the office tomorrow and will only be there on Tuesday preparing to go to Vegas, so it is unlikely to happen then.

I will look forward to seeing your pictures.

Wink

Argh ... I wish I were going this year.

No sweat man. We can pick this up when you get back and HAVE A GREAT TIME!!! Please give one toast around the table for Rhino pweeze!

 

[Rhino]

Hey Garry,

Heading out at this moment but I''ll definitely check em out. If I''m mistaken about the domes I''ll stand corrected but I had other info. I''ll look into and confirm.

Peace,

 

[aljdewey]

Date: 5/26/2006 3:47:43 PM
Author: Rhino

What perhaps annoys me about all of this is if someone (such as myself) has an opinion that differs I've been personally attacked because of it and that is just not right. I don't appreciate having my integrity called into question because I see things differently (particularly from the older thread back in March). Do you understand where I'm coming from on this Wink?

I honestly don't see where you are coming from on this, because I don't consider it a personal attack to have my opinion disagreed with. As such, I have a hard time understanding why others (yourself included) feel attacked over a simple disagreement of opinion. People can disagree with your findings/conclusions without it being a disparagement of you.

If you have one opinion and someone else has another, why does that constitute an "attack"? To me, debate is the way that people either come to consensus or realize that they won't reach consensus. Disagreeing with your opinion, or disagreeing with Marty's opinion, or disagreeing with anyone's opinion shouldn't be interpreted as 'calling one's integrity into question'. That's not what it is.

If someone says "I don't agree with your conclusions because I don't feel the test comparisons were broad enough", it's a disagreement over methodology, not a personal attack.

Edited to add: In reading back through this thread, I can readily see where the responses from one individual are far beyond what I'd consider "standard fare" disagreement, and I can see why you're bothered by it. I'll confess I wouldn't much like it either, and I think that while he may make some valid points, he could do so in a much more mature fashion, and one that is more respectful toward members in a common trade.

 

[aljdewey]

Date: 5/26/2006 5:16:26 PM
Author: Wink

Some people like the larger broader flashes from the EightStar than the smaller flashes from the H&A cut stones that I have here, and I can readily see the difference between some of the Israeli cut H&A''s that I have here and the EightStars in terms of light, but only because I have a LOT of practice at it. When I put one of Paul''s stones next to a comperable EightStar I have to weigh them to make sure I did not mix them up, even though I THINK I know which is which. Some days I will give a tiny edge to one, and some days I will give a tiny edge to the other. The differnces are very minor, and do not involve darker edges.

Wink, this really sums up well what I feel is at the heart of the issue, and mirrors my extremely limited experience with comparing them too. Every time we''ve compared, we cannot definitively pick up the differences even when we try hard, nevermind readily.

Add to that the number of really experienced folks like yourself who ALSO say "gee, even I''m hard pressed to note the differences.....to the point that I have to WEIGH them to tell them apart! That absolutely mirrors what we experienced, too.

We hear this from a bunch of really expert eyes, and then our own experiences match that too......so it''s a bit difficult for me to get behind an assertion that "90% of everyday consumers see a visible difference" when so many experts who''ve seen *thousands* of stones can''t. Maybe it goes back to how the question is being framed....."which one is brighter" (because it prompts the expectation that one IS actually brighter). Maybe it''s not the form of the question.....I dunno.

Date: 5/26/2006 5:16:26 PM
Author: Wink

I do not like the implication that painted stones are bad. I will fight it tooth and nail every time I see it. It is bad if done incorrectly. It can actually enhance the visual appearance of the stone if done correctly.

And that''s really at the heart of it for me, too. I agree that is the implication being made.....maybe unintentionally or maybe not, but the net result is the same. It is being implied.

 

[adamasgem]

Date: 5/26/2006 6:16:03 PM
Author: aljdewey

Date: 5/26/2006 3:47:43 PM
Author: Rhino

What perhaps annoys me about all of this is if someone (such as myself) has an opinion that differs I''ve been personally attacked because of it and that is just not right. I don''t appreciate having my integrity called into question because I see things differently (particularly from the older thread back in March). Do you understand where I''m coming from on this Wink?

I honestly don''t see where you are coming from on this, because I don''t consider it a personal attack to have my opinion disagreed with. As such, I have a hard time understanding why others (yourself included) feel attacked over a simple disagreement of opinion. People can disagree with your findings/conclusions without it being a disparagement of you.

If you have one opinion and someone else has another, why does that constitute an ''attack''? To me, debate is the way that people either come to consensus or realize that they won''t reach consensus. Disagreeing with your opinion, or disagreeing with Marty''s opinion, or disagreeing with anyone''s opinion shouldn''t be interpreted as ''calling one''s integrity into question''. That''s not what it is.

If someone says ''I don''t agree with your conclusions because I don''t feel the test comparisons were broad enough'', it''s a disagreement over methodology, not a personal attack.

Edited to add: In reading back through this thread, I can readily see where the responses from one individual are far beyond what I''d consider ''standard fare'' disagreement, and I can see why you''re bothered by it. I''ll confess I wouldn''t much like it either, and I think that while he may make some valid points, he could do so in a much more mature fashion, and one that is more respectful toward members in a common trade.

aljdewey, I would like to compliment you on your posts and insights..

I consider myself spanked.

It just that I have lost so much respect for some merchants in the "trade" (as well as organization(s)) and then there are some I never had any respect for at all, technically or otherwise.

There is also a lot of "history" regarding the current subject matter and those trying to promote a diametrically opposite viewpoint from their past, and reasons why, which have been addressed on other threads...

I call it like I see it... Sometimes with a nuke or two...

 

[adamasgem]

Date: 5/26/2006 6:49:11 PM
Author: aljdewey

Date: 5/26/2006 5:16:26 PM
Author: Wink

I do not like the implication that painted stones are bad. I will fight it tooth and nail every time I see it. It is bad if done incorrectly. It can actually enhance the visual appearance of the stone if done correctly.

And that''s really at the heart of it for me, too. I agree that is the implication being made.....maybe unintentionally or maybe not, but the net result is the same. It is being implied.

Implied is an understatement, in my opinion. There is a not too subtle game being played here, and a lot of us have seen right though it. I just don''t like it.

 

[belle]

Date: 5/26/2006 7:53:47 PM
Author: adamasgem

Date: 5/26/2006 6:49:11 PM
Author: aljdewey

Date: 5/26/2006 5:16:26 PM
Author: Wink

I do not like the implication that painted stones are bad. I will fight it tooth and nail every time I see it. It is bad if done incorrectly. It can actually enhance the visual appearance of the stone if done correctly.

And that''s really at the heart of it for me, too. I agree that is the implication being made.....maybe unintentionally or maybe not, but the net result is the same. It is being implied.

Implied is an understatement, in my opinion. There is a not too subtle game being played here, and a lot of us have seen right though it. I just don''t like it.

ditto.

 

[aljdewey]

I found this thread MOST interesting.......what excellent timing!

https://www.pricescope.com/community/threads/gia-brillianteering-of-the-half-facets.45748/

So, from this, I guess if the stone weren''t brillianteered, it would get an EX grade? That''s really sad.

 

[Garry H (Cut Nut)]

Date: 5/26/2006 6:10:26 PM
Author: Rhino

Hey Garry,

Heading out at this moment but I''ll definitely check em out. If I''m mistaken about the domes I''ll stand corrected but I had other info. I''ll look into and confirm.

Peace,

While you are at it Jonathon, you might like to start your research by reading what GIA did so you understand that you can not possibly approve.
They wrote an article in Gems 7 Gemology which is available on-line here http://www.gia.edu/pdfs/cut_fall2004.pdf

In it on page 211 they wrote this:

For the Brightness and Fire teams, additional
viewing devices were sometimes employed, especially
in the early stages of investigation. To test
our axially symmetric (that is, hemisphere-like)
brightness metrics, we built patterned hemispheres
(figure 7; also, see table 1 in the Gems & Gemology
Data Depository at www.gia.edu/gemsandgemology)
of various sizes (6, 12, and 16 inches—about 15, 30,
and 41 cm—in diameter) in which the diamonds
were placed while observers evaluated their relative
brightness. The results of these hemisphere
observations were also compared to results from
the more typical trade environments discussed
above (table 4, “Brightness: verification;” see also
box A). To be rigorous in our investigation, we
examined a wider range of hemispheres than we
believed were necessary solely to test our brightness
metrics. In addition, we constructed a “fire
training station,” an environment consisting of a
light source and a long tube (figure that enabled
Fire team observers to grow accustomed to seeing
finer distinctions of dispersed colors in diamonds,
and to distinguish among diamonds with different
amounts of fire. Once they were comfortable with
the fire training station, observers made evaluations
of fire in our retail-equivalent lighting
(described above) and, eventually, in our CVE (table
4, “Fire: verification”).

Now i have always assumed that you had read the article - but the comment above (and now I see much else you have written) shows you have not read it.

If you really intend to discuss issues like Diamond Dock etc, then it would be worth your while (and save us all lots of time) if you would thoroughly read it.

 

[Rhino]

Date: 5/26/2006 3:52:19 PM
Author: JohnQuixote

Date: 5/26/2006 3:23:32 PM
Author: Rhino

Date: 5/26/2006 8:35:20 AM
Author: JohnQuixote




GIA arrived at 3 drawings of painted girdles for EX by which to judge all diamonds.
I think GIA took a shortcut.

LOL ... you''re saying GIA is judging painting by 3 drawings? I''d be interested to hear where you got this from and I''d like to see the drawings that their graders use to judge all painted diamond.

Rhino,

From this article: http://lgdl.gia.edu/pdfs/estimating_painitng.pdf

The most direct way to visually assess the level of painting and/or digging out on a round brilliant is to examine the girdle profile of the diamond...Consistent with the five categories in the GIA Diamond Cut Grading System, we have divided into five levels the extent of painting and/or digging out possible on round brilliant diamonds. The illustrations in figures 4 and 5 (a full page version is available at the end of this document) show examples of the approximate extent of painting and digging out allowed for the top four cut grade categories as represented by the girdle profiles.

Figure 4. These girdle profile example iillustrate the extent of painting allowed for each of the top four cut grade categories. A diamond with a girdle profile more irregular than “severe” would not lower the cut grade beyond “fair.”

Here the 3 drawings GIA provided in their full page as painting allowances for EX grade (I added 3 for VG as well).

If there is more please elaborate for me. I''d be glad to hear it!

Hi John,

Thanks for posting the graphic. From what I am told each individual diamonds girdle is examined for the extent of painting/digging plus the impact on face up appearance. While the graphics demonstrate the extent to which each degree is allowable I don''t know for sure if the graders in the labs sit there with these drawings to determine that. Your post seemed to imply that and is how I took it. Interestingly when I stop and think about it, an accurate scan of a diamond examined in the DiamCalc software (which is basically a line art drawing) does show the extent of it. I''m not sure if that''s how the graders in the labs actually do it but I''m putting in the request to find out. I''ll let ya know what I hear.

Peace,

 

[Rhino]

Date: 5/26/2006 5:28:29 PM
Author: Garry H (Cut Nut)

Date: 5/26/2006 11:24:10 AM
Author: Rhino

Date: 5/25/2006 12:58:01 AM
Author: Garry H (Cut Nut)

Date: 5/24/2006 10:54:50 PM
Author: strmrdr

Date: 5/24/2006 10:32:10 PM
Author: Garry H (Cut Nut)
For all those who have DiamCalc and want to see what a diamond looks like in the cat liter box - here is my best approximation for the lighting in DiamCalc.

way too much head shadow compared to the DD, no cigar

Storm try the attached 46 degree dome lighting that gIA used as their model for obsured lighting.
I modeled it here with fading to the hemisphere light, which i think they would approve of.

Since this was the lighting model they used in their software ''metric'' that approximated the dealer lighting that the fluoro DD light aproximates - check it out and see if you think I have too much head shadow in the DD?

Hi Garry,

The white dome was used in some of the studies but none of the observation testing was performed with this. White dome stuff is kinda moot.

Rhino you claim to be an expert in this area, yet you really do not follow through before making your statements.
Read tha last line here and you will see that about 8% of GIA''s total observations were done thru this dome (5095).
http://www.gia.edu/pdfs/cut_table_1.pdf
http://www.gia.edu/pdfs/cut_table_1.pdf

great work I am sure John, but Wink - forget it - this is a non issue

Thanks for the links to the charts. Here is what they reported regarding the use of the domes in the Fall 2004 G&G article.

Early Observatoin Testing: Brightness and Fire

Our Brightness team examined a set of fire Research Diamonds, RD01 - RD05, for birghtness differences in the dome environments described above. We confirmed that the predictions of a specific brightness metric (the relative brightness order of hte five diamonds) matched the observations of hte Brightness team in the environment for that metric. We then used relative observation of 990 pairs of Research Diamonds (core reference set) in dealer-equivalent lighting to select the appropriate brightness metric; that is, we adjusted the modeling conditions (e.g., lighting conditions or viewing geometry) of our brightness metrics until we found one that predicted brightness ranking in the same order as the observational results.

According to the Fall G&G article the Brightness team did the examinations through these to see how they corellated but as far as I know none of the observers used it. Even if what your saying is accurate (that 8% did and I have no reason to doubt you) that means 92% didn''t causing me to stick to my view. Dome viewing while interesting = moot. To me, viewing a diamond in diffuse daylight that represents the assessment I''ll see in other diffuse daylight environements represents the most accurate determination for me personally since those are the environements people regularly find themselves in on a daily basis.

That doesn''t mean I''m not interested to see the lighting schemes you come up with in DiamCalc Garry to compare to common viewing for comparison.

Peace,

 

[Rhino]

Date: 5/26/2006 6:16:03 PM
Author: aljdewey

Date: 5/26/2006 3:47:43 PM
Author: Rhino

What perhaps annoys me about all of this is if someone (such as myself) has an opinion that differs I''ve been personally attacked because of it and that is just not right. I don''t appreciate having my integrity called into question because I see things differently (particularly from the older thread back in March). Do you understand where I''m coming from on this Wink?

I honestly don''t see where you are coming from on this, because I don''t consider it a personal attack to have my opinion disagreed with. As such, I have a hard time understanding why others (yourself included) feel attacked over a simple disagreement of opinion. People can disagree with your findings/conclusions without it being a disparagement of you.

If you have one opinion and someone else has another, why does that constitute an ''attack''? To me, debate is the way that people either come to consensus or realize that they won''t reach consensus. Disagreeing with your opinion, or disagreeing with Marty''s opinion, or disagreeing with anyone''s opinion shouldn''t be interpreted as ''calling one''s integrity into question''. That''s not what it is.

If someone says ''I don''t agree with your conclusions because I don''t feel the test comparisons were broad enough'', it''s a disagreement over methodology, not a personal attack.

Edited to add: In reading back through this thread, I can readily see where the responses from one individual are far beyond what I''d consider ''standard fare'' disagreement, and I can see why you''re bothered by it. I''ll confess I wouldn''t much like it either, and I think that while he may make some valid points, he could do so in a much more mature fashion, and one that is more respectful toward members in a common trade.

Thank you for understanding. Just for the record ... I have no bone to pick with Marty or any company nor do I have any axe to grind. While I do have my preferences and state so, you will not find me attacking or discouraging consumers out of any product from any competitor. In fact Leonid had to remind me of forum rules (not to discourage or endorse competitors products or business) because I was saying kind things about a competitors product and a particular vendor who featured it. It is not my style nor consistent with my character to bash someone else or their product to make a sale. If you recall before I was aware of that forum rule I would regularly comment on diamonds that consumers were asking opinions on. When I knew the stone was good I would say so regardless of who was selling it and if the stone was not I simply would not comment at all. I think/hope you know this about me.

Peace,

 

[Rhino]

Date: 5/26/2006 7:42:54 PM
Author: adamasgem

Date: 5/26/2006 6:16:03 PM
Author: aljdewey

Date: 5/26/2006 3:47:43 PM
Author: Rhino

What perhaps annoys me about all of this is if someone (such as myself) has an opinion that differs I''ve been personally attacked because of it and that is just not right. I don''t appreciate having my integrity called into question because I see things differently (particularly from the older thread back in March). Do you understand where I''m coming from on this Wink?

I honestly don''t see where you are coming from on this, because I don''t consider it a personal attack to have my opinion disagreed with. As such, I have a hard time understanding why others (yourself included) feel attacked over a simple disagreement of opinion. People can disagree with your findings/conclusions without it being a disparagement of you.

If you have one opinion and someone else has another, why does that constitute an ''attack''? To me, debate is the way that people either come to consensus or realize that they won''t reach consensus. Disagreeing with your opinion, or disagreeing with Marty''s opinion, or disagreeing with anyone''s opinion shouldn''t be interpreted as ''calling one''s integrity into question''. That''s not what it is.

If someone says ''I don''t agree with your conclusions because I don''t feel the test comparisons were broad enough'', it''s a disagreement over methodology, not a personal attack.

Edited to add: In reading back through this thread, I can readily see where the responses from one individual are far beyond what I''d consider ''standard fare'' disagreement, and I can see why you''re bothered by it. I''ll confess I wouldn''t much like it either, and I think that while he may make some valid points, he could do so in a much more mature fashion, and one that is more respectful toward members in a common trade.

aljdewey, I would like to compliment you on your posts and insights..

I consider myself spanked.

It just that I have lost so much respect for some merchants in the ''trade'' (as well as organization(s)) and then there are some I never had any respect for at all, technically or otherwise.

There is also a lot of ''history'' regarding the current subject matter and those trying to promote a diametrically opposite viewpoint from their past, and reasons why, which have been addressed on other threads...

I call it like I see it... Sometimes with a nuke or two...

Hi Marty,

I invite you to call me personally so I can share some of this history with you. There are details I am sure you have not heard which I''d like to share with you so we can iron this out. This is personal so its not to be posted publicly however I really don''t care cause I have nothing to hide. I''m off on Sunday''s and Monday''s and if you don''t have my cell or home # you can get it from Bill. I''d be happy to talk with you. As stated to Aljdewey above, I am not on some campaign against any company, individual or diamond for that matter. Sure I''ve had differences with folks we know in common but if you search among the archives on this forum and others I''ve never put down another person''s product nor the vendor featuring it. In fact I have said kind and positive things over the years. My faith teaches me to forgive and forget and I attempt to always put this principal into practice in my daily life.

Regards,

 

[adamasgem]

Date: 5/27/2006 5:29:15 PM
Author: Rhino

Hi Marty,

I invite you to call me personally so I can share some of this history with you. There are details I am sure you have not heard which I''d like to share with you so we can iron this out. This is personal so its not to be posted publicly however I really don''t care cause I have nothing to hide. I''m off on Sunday''s and Monday''s and if you don''t have my cell or home # you can get it from Bill. I''d be happy to talk with you. As stated to Aljdewey above, I am not on some campaign against any company, individual or diamond for that matter. Sure I''ve had differences with folks we know in common but if you search among the archives on this forum and others I''ve never put down another person''s product nor the vendor featuring it. In fact I have said kind and positive things over the years. My faith teaches me to forgive and forget and I attempt to always put this principal into practice in my daily life.

Regards,

Will do.. Thanks for the invite...