No need to be afraid, Valeria. I was just toying with John, but I would never dare do that to you.
I will try to answer your question in another way, Rockdoc,Date: 2/8/2005 11:462 PM
Author: RockDoc
Paul & Rhino
As you all know I''ve been preaching about girdles being foundation of a well cut stone.
In Rhino''s first posting he mentions a 3.5% girdle....Since you two have the disc, and mine hasn''t arrived yet... what is your take on how significantly the girdle come into analysis.
The eightstars have incredibly cut girdles as well as very tight roundness specs. Has AGS done any comparative studies on the variations of the girdle?
Interesting to hear Paul''s opinion on how the girdle may affect light retrun on if either the GIA or AGS is paying attention to that.
When the final software comes out, by both major labs, it will be fascinating to see how they deal with this and what the differences are like in comparing them to each other.
Exciting stuff happening!
Rockdoc
Hey Rockdaddy!
Variances will play a role as well doc. I''m not sure how much tolerance they''ll allow to be considered *ideal* but that will be of interest as well. Bill ... you are to be credited with bringing this to public awareness years ago via the forums even when noone was talking about it. Indeed it has been our discussions that have prompted me into further study of these things as well.
Thanks man! I always enjoy your posts as well.
In answer to your inquiry Rock... ABSOLUTELY YES they are going to take upper girdles angles into consideration. I''d have to verify but I believe once the upper girdles hit 43 degrees, that''s when things begin to spiral downward. Email or pm me for more details.Date: 2/8/2005 11:462 PM
Author: RockDoc
Paul & Rhino
As you all know I''ve been preaching about girdles being foundation of a well cut stone.
In Rhino''s first posting he mentions a 3.5% girdle....Since you two have the disc, and mine hasn''t arrived yet... what is your take on how significantly the girdle come into analysis.
The eightstars have incredibly cut girdles as well as very tight roundness specs. Has AGS done any comparative studies on the variations of the girdle?
Interesting to hear Paul''s opinion on how the girdle may affect light retrun on if either the GIA or AGS is paying attention to that.
When the final software comes out, by both major labs, it will be fascinating to see how they deal with this and what the differences are like in comparing them to each other.
Exciting stuff happening!
Rockdoc
Greetings Sir John,Date: 2/9/2005 12:158 AM
Author: JohnQuixote
The CD we received had nothing burned on it (maybe we got the ultra-duper secret version).We requested another.
So - While we''ve got Rhino and Paul looking - Guys, I hope you don''t mind a question...
I am encouraged by the discussions of minor facets. However, I hope AGS intends to be more precise than GIA. I know you''re looking at cutting guidelines, but do either of you see any hints about how the minors will be measured incrementally? For instance, will they treat length (or depth) in conventional increments of 1% ?
In the minor facet measurements, particularly the lower girdles, those IMO should be looked at the closest as they will impact the appearance more than any of the other minors. I''m going to forward this question to someone who''ll give me a more definite answer though.Yes but in your illustration the increments are not just 1% but an entire 4% (from 78-82%). I do not believe AGS will round to the nearest 5%. That IMO would be absurd and defeat the purpose. If that were the case then a stone would either get 75% lg''s or 80% lg''s or 85% and those increments are way too broad. As soon as I get an email back from my contact I''ll forward the answer here.
First, I have a stupid question ......what is the " " I see that on a lot of messages and not sure how to read or interpret it.Date: 2/9/2005 11:598 AM
Author: Garry H (Cut Nut)
I have not read all this yet, but Roc the AGS system gives parameters for ''candidates'' in the same way HCA does.
But they then go further to do individual stone testing with DiamCalc and other tools based on 3D scans. Girdle painting or gouging with positive or negative effects (they can be either, depending on oither parameters) will of course be taken into account.
It seems to me AGs have moved to a new level. Until the OctoNus system is released this will be the best grading system available.
Date: 2/9/2005 49:44 PM
Author: Rhino
Yes but in your illustration the increments are not just 1% but an entire 4% (from 78-82%). I do not believe AGS will round to the nearest 5%. That IMO would be absurd and defeat the purpose. If that were the case then a stone would either get 75% lg''s or 80% lg''s or 85% and those increments are way too broad. As soon as I get an email back from my contact I''ll forward the answer here. Peace,
Date: 2/9/2005 92:38 PM
Author: RockDoc
From Rhino
In answer to your inquiry Rock... ABSOLUTELY YES they are going to take upper girdles angles into consideration. I''d have to verify but I believe once the upper girdles hit 43 degrees, that''s when things begin to spiral downward. Email or pm me for more details.
Rhino
I meant the actual girdle, not the upper girdles...and by 3.5% which girdle measurement are they talking about?
finally we get some common sense - ags will measure rounds at the 16 thick parts - o this will stop cheating and makes Fred''s warping redundant - it also brings one more US lab into line with the rest of the world (only 1 biggie to go).
now all stones will be measured the same - there i no value in measuring princess or emeral cuts at the girdle valley!!!
many ideals even the really good H&A''s currently vary most commonly from 0.7 . Weknow the girdle isn''t uniform, so seems they should be reporting not only the variances at the halves etc, but also come up with a uniform variance standard as well.
Additionally I hope they will propose a standard for the girdles on fancy shapes as well. I''ve seen some damn thick pear tips,
maybe deduct for variances that differ over a certain percentage. I''m sure we all agree that tips of marquises and pears, if the girdle is cut too think can be a durability issue in normal wear, and for setters too.
Is there any mention in the AGS material that deals with indented naturals?
the new stuff only concerns the cut grades not ''surface features''
Rockdoc
I definitely do not agree. It is a ''communist'' way of thinking.
Rhino, you of all pupils,Date: 2/9/2005 49:44 PM
Author: Rhino
I do not believe AGS will round to the nearest 5%. That IMO would be absurd and defeat the purpose. If that were the case then a stone would either get 75% lg''s or 80% lg''s or 85% and those increments are way too broad. As soon as I get an email back from my contact I''ll forward the answer here.
Peace,
LOL... that''s funny Rock. When I first saw that too in posts and messages I thought it was perhaps an abbreviation for "NO BULLS#%T". It''s actually part of the code generated on the server when we post responses and I think is inserted behind the scenes on a line break. Leonid will know for sure. If you take note it only happens when someone is quoted and pulls that data off the server.
Now THAT is exactly the question that ran through my head when I read Gary''s comment above.
No kidding. I wasn''t aware that GIA will be rounding again.Date: 2/9/2005 8:59:41 PM
Author: JohnQuixote
Date: 2/9/2005 49:44 PM
Author: Rhino
Yes but in your illustration the increments are not just 1% but an entire 4% (from 78-82%). I do not believe AGS will round to the nearest 5%. That IMO would be absurd and defeat the purpose. If that were the case then a stone would either get 75% lg''s or 80% lg''s or 85% and those increments are way too broad. As soon as I get an email back from my contact I''ll forward the answer here. Peace,
Rhino - I cannot tell from your comments if you realize that this is exactly how GIA will be treating the increments... Were you aware of that?
I realize the illustration I posted was 4% wide: The reason for that illustration was to demonstrate GIA''s impending plan (increments of 5%)... So, in case you didn''t pick it up before, GIA will treat both 78% and 82% as 80%.
It''s good to know AGS will not follow that model. I have always maintained that 1% is perfectly acceptable (and logical).
Girdle thickness at the bezels.Date: 2/9/2005 92:38 PM
Author: RockDoc
From Rhino
In answer to your inquiry Rock... ABSOLUTELY YES they are going to take upper girdles angles into consideration. I''d have to verify but I believe once the upper girdles hit 43 degrees, that''s when things begin to spiral downward. Email or pm me for more details.
Rhino
I meant the actual girdle, not the upper girdles...and by 3.5% which girdle measurement are they talking about?
Not that I''ve seen. Bill ... is your email the same?
Date: 2/10/2005 3:55:58 PM
Author: Rhino
No kidding. I wasn''t aware that GIA will be rounding again.I don''t like the sounds of that. For an H&A purist that is *certainly* not good for the reason you pointed out in the graphic you posted. Once those lower girdles are lengthened to a certain amount, that''s when you start to get the clefts in the hearts.
While on that subject ... clefts in the hearts is no big whoop to me *really*. The reason I say this is because it is the *face up* appearance that is and will be judged and graded by the labs and there are now some super ideals with *no hearts* that many people who have seen them even like them better than H&A''s. There is an excellent level of precision to be observed in both face up and face down positions under a scope but no hearts (I''m not talking 57 facet rounds though), but even in 57 facet rounds, there are many people who enjoy the appearance of rounds cut with longer lower girdles.
My personal preference ... I don''t like em too long or too short. I definitely believe there is a place you gotta draw the line. An ever so tiny cleft begins to form around the 80% length but that isn''t something that would make or break it especially if the balance of fire and scintillation in the *face up* appearance isn''t affected. I find that the longer lg''s contribute to increased scintillation in direct light conditions. If you lengthen them too much though fire/dispersion can take a hit at the expense of increased scintillation.
Peace,
Date: 2/10/2005 53:51 AM
Author: Paul-Antwerp
I definitely do not agree. It is a ''communist'' way of thinking.
Grading reports and labs is a business, and in order to improve the quality of their product, they have to compete. Competing also means differentiating their product, according to the way they perceive the demand on the market.
Uniformisation will stop the drive to improve the product. Furthermore, there will then be a need for a mantle-organisation, that controls whether every lab stays in line. In the end, you are only creating one big bureaucracy, and no value for the consumer.
I hope that this short answer is sufficiently clear.
Live long,
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