GIA Excellent = HCA 6!

[diagem]

Date: 3/9/2008 11:00:33 AM
Author: strmrdr
here ya go... ags1 takes a hit in dispersion due too the shallow upper girdles most likely.

This image is at 40.8P ? You sure?

 

[strmrdr]

Date: 3/9/2008 11:06:46 AM
Author: DiaGem

Date: 3/9/2008 11:00:33 AM
Author: strmrdr
here ya go... ags1 takes a hit in dispersion due too the shallow upper girdles most likely.

This image is at 40.8P ? You sure?

yep

 

[strmrdr]

80lgf% goes much better with that combo...

 

[WinkHPD]

I have some comments based on the "gem" presented.

In my opinion, the use of the term "Ideal" is grossly misused in the trade. In this case Blue Nile is calling a stone Ideal that would not qualify under the old rules when a diamond needed a table of 53 - 57 (or 57.5 depending on which lab you used) along with other parameters to qualify.

Since the new systems came out some wider tables are included, but this stone does NOT qualify as an Ideal by AGS and GIA does not use the term, so by who''s auspices does Blue Nile deem this to be an Ideal stone?

Someone commented that GIA grades by observation. That is incorrect as Garry pointed out. GIA arrived at their system using observers, the majority of whom were in the trade which may have (MAY HAVE, comment not indictment) introduced some bias towards the manufacturers preferences, especially the mass manufacturers. That having been said, GIA now grades by the set of parameters arrived at using Sarin Scans to determine the cut grade other than for establishing polish and symmetry grades. It is patently obvious that this diamond was cut for weight retention and not for beauty as it was cut for steepest and deepest allowable parameters.

One point not yet mentioned that I think deserves mention is that with these angles the gem stone may well entrap color and look more like a K or L than a J. One would need to see the stone to determine if this is the case, but I think it a distinct possibility.

Wink

 

[diagem]

Date: 3/9/2008 5:03:36 PM
Author: Wink
I have some comments based on the 'gem' presented.

In my opinion, the use of the term 'Ideal' is grossly misused in the trade. In this case Blue Nile is calling a stone Ideal that would not qualify under the old rules when a diamond needed a table of 53 - 57 (or 57.5 depending on which lab you used) along with other parameters to qualify.

Wink..., can you say who has exclusivity on the term "ideal"?

Since the new systems came out some wider tables are included, but this stone does NOT qualify as an Ideal by AGS and GIA does not use the term, so by who's auspices does Blue Nile deem this to be an Ideal stone?

Someone commented that GIA grades by observation. That is incorrect as Garry pointed out. GIA arrived at their system using observers, the majority of whom were in the trade which may have (MAY HAVE, comment not indictment) introduced some bias towards the manufacturers preferences, especially the mass manufacturers. That having been said, GIA now grades by the set of parameters arrived at using Sarin Scans to determine the cut grade other than for establishing polish and symmetry grades. It is patently obvious that this diamond was cut for weight retention and not for beauty as it was cut for steepest and deepest allowable parameters.

To say that this Diamond was cut for weight retention and NOT for beauty is a bit harsh in my opinion..., at 61.9% depth including a shallow crown angle of 33.5 deg. could mean it was cut for weight retention and could mean it was not, (it would depend on the rough Diamond it started with) which we dont know for a fact! But to say this Diamond was NOT cut for beauty while it earned a cut grade of triple excellent from GIA is "again" a bit harsh..., cutters work darn hard to reach this level of cutting and your comment is just not fair!

One point not yet mentioned that I think deserves mention is that with these angles the gem stone may well entrap color and look more like a K or L than a J. One would need to see the stone to determine if this is the case, but I think it a distinct possibility.

In my experience..., GIA would not grade a Diamond which appears K-L as a J..., they are pretty harsh on these colors...



Wink

Wink..., if this Diamond was cut for obvious weight retention..., I would think the cutter would not easily give up the 1.50 carat magic number...

 

[Garry H (Cut Nut)]

DG I think Wink can be right about the bad cut having a lower "appearance" for face up colour.
These two stones have identical absorption spectra loaded into DiamCalc and are around the colour we are discussing.

As a second smaller stone from a piece of large octahedral 6-10ct ish rough this stone would be cut for weight. In a case like this a 1.5ct would not have been an option. Also there is not a lot of difference in price for 1.44 and 1.5ct J SI2. Next week Martin will combine the 1 and 1.5 grids anyway

 

[Garry H (Cut Nut)]

Date: 3/9/2008 5:30:23 PM
Author: DiaGem

Date: 3/9/2008 5:03:36 PM
Author: Wink
I have some comments based on the ''gem'' presented.

In my opinion, the use of the term ''Ideal'' is grossly misused in the trade. In this case Blue Nile is calling a stone Ideal that would not qualify under the old rules when a diamond needed a table of 53 - 57 (or 57.5 depending on which lab you used) along with other parameters to qualify.

Wink..., can you say who has exclusivity on the term ''ideal''?

Interesting story in Al Gilbertsons book about how ''ideal'' came about.

The word ''perfect'' was being bandied about by marketers in the 1930''s and was banned by the FTC in 1938.

''ideal'' was the next best (worst depending on your point of view) accepted term.

This adds weight to the recent discussion on another thread about the negative impact on consumer confidence of the use of such absolute terminology, and the deletirious impact on the toher brands that each successsive such claims cause.

 

[WinkHPD]

Date: 3/9/2008 5:30:23 PM
Author: DiaGem

Date: 3/9/2008 5:03:36 PM

Author: Wink

I have some comments based on the ''gem'' presented.


In my opinion, the use of the term ''Ideal'' is grossly misused in the trade. In this case Blue Nile is calling a stone Ideal that would not qualify under the old rules when a diamond needed a table of 53 - 57 (or 57.5 depending on which lab you used) along with other parameters to qualify.


Wink..., can you say who has exclusivity on the term ''ideal''?

Obviously not since it is so often misused to describe stones that are not ideal in any official grade, even the old ones that we used to use as taught by both GIA and AGS with minor variations prior to the new grades coming out.


Since the new systems came out some wider tables are included, but this stone does NOT qualify as an Ideal by AGS and GIA does not use the term, so by who''s auspices does Blue Nile deem this to be an Ideal stone?


Someone commented that GIA grades by observation. That is incorrect as Garry pointed out. GIA arrived at their system using observers, the majority of whom were in the trade which may have (MAY HAVE, comment not indictment) introduced some bias towards the manufacturers preferences, especially the mass manufacturers. That having been said, GIA now grades by the set of parameters arrived at using Sarin Scans to determine the cut grade other than for establishing polish and symmetry grades. It is patently obvious that this diamond was cut for weight retention and not for beauty as it was cut for steepest and deepest allowable parameters.



To say that this Diamond was cut for weight retention and NOT for beauty is a bit harsh in my opinion..., at 61.9% depth including a shallow crown angle of 33.5 deg. could mean it was cut for weight retention and could mean it was not, (it would depend on the rough Diamond it started with) which we dont know for a fact! But to say this Diamond was NOT cut for beauty while it earned a cut grade of triple excellent from GIA is ''again'' a bit harsh..., cutters work darn hard to reach this level of cutting and your comment is just not fair!

Perhaps it is just my personal bias against super steep deep combinations that will not have the beauty of a stone cut for maximum light return and scintillation.

One point not yet mentioned that I think deserves mention is that with these angles the gem stone may well entrap color and look more like a K or L than a J. One would need to see the stone to determine if this is the case, but I think it a distinct possibility.


In my experience..., GIA would not grade a Diamond which appears K-L as a J..., they are pretty harsh on these colors...

Diamond colors age graded from the side, through the body of the diamond, not from the top. Tom Tashey of PGS has long advocated that diamonds should have an official color grade and an apparent color grade as it looks from the top to reward those stones that look better than their official color and punish those that look worse. (He says it much more eloquently than I do and does not use my terminology, I am paraphrasing not quoting his comments.)


Wink

Wink..., if this Diamond was cut for obvious weight retention..., I would think the cutter would not easily give up the 1.50 carat magic number...

I can not know this for a fact, but I surmise that it was not reachable or it would have been. This is just my guess, I have no knowledge of the rough. It is my opinion that this type of stone is the problem with the GIA system that does not make use of modern technology that can judge accurately the light performance of the gem with ray tracing. It is why I have become a strong advocate for the AGS system that grades each stone based on its light performance, not on a fixed set of parameters that in some combinations may not deserve the top cut grades.

Please remember that these are my opinions without having seen the gem in question, but from the numbers I do not believe that it would warrant a top grade if actual performance were measured. I am sure it is much prettier than some of the stones I would see at the mall, but not nearly as beautiful as it could be with a better crown and pavilion angle combination.

Wink

 

[ginzagirl]

Hi,

I''m new and this question has nothing to do with this topic but if Phoenixgirl or anyone here can post a larger picture of her wedding band, I''d love to see it.

Thanks!

 

[diagem]

Date: 3/9/2008 11:28:58 PM
Author: Garry H (Cut Nut)
DG I think Wink can be right about the bad cut having a lower ''appearance'' for face up colour.
These two stones have identical absorption spectra loaded into DiamCalc and are around the colour we are discussing.

Could be..., but it will need to be verified on a stone per stone basis..., I still stand on the fact that if the Diamond would show a lower face-up appearance in terms of color..., GIA would penalize it..., I have noticed it on quite a few occasions!

As a second smaller stone from a piece of large octahedral 6-10ct ish rough this stone would be cut for weight. In a case like this a 1.5ct would not have been an option. Also there is not a lot of difference in price for 1.44 and 1.5ct J SI2. Next week Martin will combine the 1 and 1.5 grids anyway

Speculation Garry...,
Cutters don''t usually cut for weight only while trying to achieve a triple X cut grade...

Depends on your view..., 40-30% is "not a lot of difference"?

 

[diagem]

Date: 3/9/2008 11:59:34 PM
Author: Wink

Date: 3/9/2008 5:30:23 PM
Author: DiaGem

Date: 3/9/2008 5:03:36 PM

Author: Wink

I have some comments based on the ''gem'' presented.


In my opinion, the use of the term ''Ideal'' is grossly misused in the trade. In this case Blue Nile is calling a stone Ideal that would not qualify under the old rules when a diamond needed a table of 53 - 57 (or 57.5 depending on which lab you used) along with other parameters to qualify.


Wink..., can you say who has exclusivity on the term ''ideal''?

Obviously not since it is so often misused to describe stones that are not ideal in any official grade, even the old ones that we used to use as taught by both GIA and AGS with minor variations prior to the new grades coming out.




Since the new systems came out some wider tables are included, but this stone does NOT qualify as an Ideal by AGS and GIA does not use the term, so by who''s auspices does Blue Nile deem this to be an Ideal stone?


Someone commented that GIA grades by observation. That is incorrect as Garry pointed out. GIA arrived at their system using observers, the majority of whom were in the trade which may have (MAY HAVE, comment not indictment) introduced some bias towards the manufacturers preferences, especially the mass manufacturers. That having been said, GIA now grades by the set of parameters arrived at using Sarin Scans to determine the cut grade other than for establishing polish and symmetry grades. It is patently obvious that this diamond was cut for weight retention and not for beauty as it was cut for steepest and deepest allowable parameters.



To say that this Diamond was cut for weight retention and NOT for beauty is a bit harsh in my opinion..., at 61.9% depth including a shallow crown angle of 33.5 deg. could mean it was cut for weight retention and could mean it was not, (it would depend on the rough Diamond it started with) which we dont know for a fact! But to say this Diamond was NOT cut for beauty while it earned a cut grade of triple excellent from GIA is ''again'' a bit harsh..., cutters work darn hard to reach this level of cutting and your comment is just not fair!

Perhaps it is just my personal bias against super steep deep combinations that will not have the beauty of a stone cut for maximum light return and scintillation.

OK..., but it is different than saying, "...this diamond was cut for weight retention and not for beauty..."
wink..., I dont know how close you are to the cutting procedure or cutters..., but to achieve a triple X cut grade by GIA is not an easy task..., and I am putting am emphasis on the "polish" grade!
While on this subject..., cutting for maximum light return and scintillation are not the only qualities which make a Diamond "beautiful"

One point not yet mentioned that I think deserves mention is that with these angles the gem stone may well entrap color and look more like a K or L than a J. One would need to see the stone to determine if this is the case, but I think it a distinct possibility.


In my experience..., GIA would not grade a Diamond which appears K-L as a J..., they are pretty harsh on these colors...

Diamond colors age graded from the side, through the body of the diamond, not from the top. Tom Tashey of PGS has long advocated that diamonds should have an official color grade and an apparent color grade as it looks from the top to reward those stones that look better than their official color and punish those that look worse. (He says it much more eloquently than I do and does not use my terminology, I am paraphrasing not quoting his comments.)


Are you saying this specifically about GIA color grading procedures?? If yes..., I would agree with you that it''s the GIA "procedure" !
As I said before a few times..., GIA need to work according to a "system"! But I (personally) have been witnessing more and more that face-up appearance is being taken into account. (Could be GIA color-grading is assisted by a type of colorimeter device??

)
As far as grading color in general..., most industry professionals do take into account more that JUST side/body color grading! Remember..., most dont NEED to grade according to A system vs. the laboratory graders who do need...

Wink

Wink..., if this Diamond was cut for obvious weight retention..., I would think the cutter would not easily give up the 1.50 carat magic number...

I can not know this for a fact, but I surmise that it was not reachable or it would have been. This is just my guess, I have no knowledge of the rough. It is my opinion that this type of stone is the problem with the GIA system that does not make use of modern technology that can judge accurately the light performance of the gem with ray tracing. It is why I have become a strong advocate for the AGS system that grades each stone based on its light performance, not on a fixed set of parameters that in some combinations may not deserve the top cut grades.

Wink..., there are just too many factors which a cutter must take into account for us to reach this type of conclusion....

Please remember that these are my opinions without having seen the gem in question, but from the numbers I do not believe that it would warrant a top grade if actual performance were measured. I am sure it is much prettier than some of the stones I would see at the mall, but not nearly as beautiful as it could be with a better crown and pavilion angle combination.

Again..., beauty is subjective..., as far as "could be better"..., It always can..., nobody guarantees that the top-cut grades of today will stay..., I wouldnt be at all surprised that tomorrow they might be just average...

Wink

Now on a side note...
Nearly most or the majority of Diamond cutters or manufacturers are cutting Diamonds (these days) to reach an end result which will be a balance between maximum weight retention and best cut, appearance (or beauty)..., at the going rough Diamond prices of today (and they keep climbing...)..., if you dont..., you''re out of business..., FAST!!!

 

[Garry H (Cut Nut)]

DG check Rap on the J SI2 - it is a small % and the premium for 1.40+ woudld cover it.

Date: 3/10/2008 5:25:02 AM
Author: DiaGem

Date: 3/9/2008 11:59:34 PM
Author: Wink

Date: 3/9/2008 5:30:23 PM
Author: DiaGem

Date: 3/9/2008 5:03:36 PM

Author: Wink


Diamond colors age graded from the side, through the body of the diamond, not from the top. Tom Tashey of PGS has long advocated that diamonds should have an official color grade and an apparent color grade as it looks from the top to reward those stones that look better than their official color and punish those that look worse. (He says it much more eloquently than I do and does not use my terminology, I am paraphrasing not quoting his comments.)


Are you saying this specifically about GIA color grading procedures?? If yes..., I would agree with you that it''s the GIA ''procedure'' !
As I said before a few times..., GIA need to work according to a ''system''! But I (personally) have been witnessing more and more that face-up appearance is being taken into account. (Could be GIA color-grading is assisted by a type of colorimeter device??

)
As far as grading color in general..., most industry professionals do take into account more that JUST side/body color grading! Remember..., most dont NEED to grade according to A system vs. the laboratory graders who do need...

Wink

Wink

The new Gem Adviser with colour will make this face up vs side view color difference very obvious and apparent for different cuts and cut qualities.

Soon Gem Adviser will convey every relevant bit of information.

DG you probably need to make that huge $400-500 investment before the price goes up again and the Dollar falls further..

 

[diagem]

Date: 3/10/2008 5:46:27 AM
Author: Garry H (Cut Nut)
DG check Rap on the J SI2 - it is a small % and the premium for 1.40+ woudld cover it.

OK..., sorry..., not 40-30%..., but about 20%+/- any way you want to calculate...

The new Gem Adviser with colour will make this face up vs side view color difference very obvious and apparent for different cuts and cut qualities.

Soon Gem Adviser will convey every relevant bit of information.

DG you probably need to make that huge $400-500 investment before the price goes up again and the Dollar falls further..

Could GIA be using this "new" Gem Adviser???

As I told you Garry previously..., I am waiting for tech. support on DC...

I tried contacting Serg..., but had no success...

 

[Serg]

Date: 3/10/2008 6:55:45 AM
Author: DiaGem

Date: 3/10/2008 5:46:27 AM
Author: Garry H (Cut Nut)
DG check Rap on the J SI2 - it is a small % and the premium for 1.40+ woudld cover it.

OK..., sorry..., not 40-30%..., but about 20%+/- any way you want to calculate...

The new Gem Adviser with colour will make this face up vs side view color difference very obvious and apparent for different cuts and cut qualities.

Soon Gem Adviser will convey every relevant bit of information.

DG you probably need to make that huge $400-500 investment before the price goes up again and the Dollar falls further..

Could GIA be using this ''new'' Gem Adviser???

As I told you Garry previously..., I am waiting for tech. support on DC...

I tried contacting Serg..., but had no success...

re:As I told you Garry previously..., I am waiting for tech. support on DC...
I tried contacting Serg..., but had no success...

What do you mean? I think I saw your letter about HP only and sent asnwer

 

[diagem]

Date: 3/10/2008 7:01:59 AM
Author: Serg

Date: 3/10/2008 6:55:45 AM
Author: DiaGem

Date: 3/10/2008 5:46:27 AM
Author: Garry H (Cut Nut)
DG check Rap on the J SI2 - it is a small % and the premium for 1.40+ woudld cover it.

OK..., sorry..., not 40-30%..., but about 20%+/- any way you want to calculate...

The new Gem Adviser with colour will make this face up vs side view color difference very obvious and apparent for different cuts and cut qualities.

Soon Gem Adviser will convey every relevant bit of information.

DG you probably need to make that huge $400-500 investment before the price goes up again and the Dollar falls further..

Could GIA be using this ''new'' Gem Adviser???

As I told you Garry previously..., I am waiting for tech. support on DC...

I tried contacting Serg..., but had no success...

re:As I told you Garry previously..., I am waiting for tech. support on DC...
I tried contacting Serg..., but had no success...

What do you mean? I think I saw your letter about HP only and sent asnwer

Hi Serg..., HP? Never received any reply...

 

[Serg]

Date: 3/10/2008 7:14:02 AM
Author: DiaGem

Date: 3/10/2008 7:01:59 AM
Author: Serg

Date: 3/10/2008 6:55:45 AM
Author: DiaGem

Date: 3/10/2008 5:46:27 AM
Author: Garry H (Cut Nut)
DG check Rap on the J SI2 - it is a small % and the premium for 1.40+ woudld cover it.

OK..., sorry..., not 40-30%..., but about 20%+/- any way you want to calculate...

The new Gem Adviser with colour will make this face up vs side view color difference very obvious and apparent for different cuts and cut qualities.

Soon Gem Adviser will convey every relevant bit of information.

DG you probably need to make that huge $400-500 investment before the price goes up again and the Dollar falls further..

Could GIA be using this ''new'' Gem Adviser???

As I told you Garry previously..., I am waiting for tech. support on DC...

I tried contacting Serg..., but had no success...

re:As I told you Garry previously..., I am waiting for tech. support on DC...
I tried contacting Serg..., but had no success...

What do you mean? I think I saw your letter about HP only and sent asnwer

Hi Serg..., HP? Never received any reply...

reply was,
"Sorry, we have not now any support for HP in USA, we do not sell HP to USA now"

DC is not HP
DC is just simple software. HP is scanner. For DC we have internet support , it is impossible for scanners

 

[diagem]

Date: 3/10/2008 7:22:21 AM
Author: Serg

reply was,
''Sorry, we have not now any support for HP in USA, we do not sell HP to USA now''

DC is not HP
DC is just simple software. HP is scanner. For DC we have internet support , it is impossible for scanners

Serg..., you are not on the same wave as I am..., maybe Garry will fill you in....

 

[diagem]

Thanks Garry..., and Serg..., sorry if I confused you..., I am confused myself when it comes to HIGH-TECH