3ct stone graded AGS0 ideal, but only 3.1 on HCA

[KristyDarling]

Hi there,

It almost seems like the definition of ideal changes depending on whom you ask!

I have a very nice vendor bringing in a stone for review...it''s a 3.22ct GSI1 graded ideal 0 by AGS in all 3 areas: polish, symmetry, and proportions. However, when I entered the specs into HCA, it scored a disappointing 3.1 and got "Very Good" on light return, fire, and spread. Scintillation scored an even more disappointing "Good." Shouldn''t an AGS0 stone have scored "Excellent" on most of these parameters?? Anyway, I''ll let you all be the judge:

Cert date: Dec 2004
Color: G
Clarity: SI1
Cut: AGS Ideal 0, sym/pol/proportions = all 0
Wt: 3.228
Depth %: 61.4
Table %: 56%
Crown ang: 35.3
Pav ang: 41.0
Crown: 15.5%
Pav: 43.4%
Gird: .7 to 1.3%, faceted
Culet: pointed

Kind of a deep stone, no? My vendor will Sarin and Idealscope the stone so I''ll be getting more info, but so far, I''m feeling a bit uncertain about this one. Anyone care to weigh in? I need help!!!!

Thanks so much!
Kristy

 

[belle]

the ''old'' ags0''s were a bit more lenient. i think you will find that the ''new'' ones will score better.

 

[KristyDarling]

hi belle!

the vendor said he recalculated the specs using AGS'' new, stricter standards and said it''s still considered an AGS0. I trust this vendor because he''s very highly regarded here...i''m just confused because of the discrepancy with HCA and the fact that the stone just seems too deep, based on the numbers. Is there something I don''t know, like is the ideal range for larger stones somehow different?

 

[Demelza]

Are you in a position where you can view the stone in person? Has the vendor seen it? Yes, it does look like a deep stone based on the crown and pavilion angles, but perhaps it works nonetheless. To my knowledge, the ideal range for larger stones is no different from that of smaller stones.

 

[Regular Guy]

Date: 10/11/2005 11:26:22 AM
Author: Demelza
Are you in a position where you can view the stone in person? Has the vendor seen it? Yes, it does look like a deep stone based on the crown and pavilion angles, but perhaps it works nonetheless. To my knowledge, the ideal range for larger stones is no different from that of smaller stones.

Kristy (earlier mis-addressed this to Demezela),

Although I understand the new AGS0 includes elements that are effectively "non-calcuable," as for example, measures of light performance that could include direct observation, only possible with the diamond in hand...neverthess...to the extent that revised angles are iterated, I understand these angles are essentially presented and overlaid visually, when you run the HCA now, here. Since you can see how this stones parameters are outside the box, with the box intending to represent what the ostensible parameters are...perhaps you can ask your trusted vendor to account for the specific difference. As they say, the devil's in the details. It's best to both trust, and verify.

Regards,

 

[Demelza]

Date: 10/11/2005 12:00:31 PM
Author: Regular Guy

Date: 10/11/2005 11:26:22 AM

Author: Demelza

Are you in a position where you can view the stone in person? Has the vendor seen it? Yes, it does look like a deep stone based on the crown and pavilion angles, but perhaps it works nonetheless. To my knowledge, the ideal range for larger stones is no different from that of smaller stones.

Demelza,


Although I understand the new AGS0 includes elements that are effectively ''non-calcuable,'' as for example, measures of light performance that could include direct observation, only possible with the diamond in hand...neverthess...to the extent that revised angles are iterated, I understand these angles are essentially presented and overlaid visually, when you run the HCA now, here. Since you can see how this stones parameters are outside the box, with the box intending to represent what the ostensible parameters are...perhaps you can ask your trusted vendor to account for the specific difference. As they say, the devil''s in the details. It''s best to both trust, and verify.


Regards,

I wasn''t suggesting she just trust the vendor blindly. I was just asking whether the vendor had seen the stone and whether she would be able to view the stone herself. If she does trust the vendor and he/she thinks it''s a stone worth seeing, I was suggesting that it might be worth a look either to confirm or reject the vendor''s conclusion rather than eliminating the stone based on numbers alone. Especially since it''s very hard these days to find stones in this size range.

 

[Regular Guy]

Date: 10/11/2005 12:13:22 PM
Author: Demelza

Date: 10/11/2005 12:00:31 PM
Author: Regular Guy

Date: 10/11/2005 11:26:22 AM

Author: Demelza

Are you in a position where you can view the stone in person? Has the vendor seen it? Yes, it does look like a deep stone based on the crown and pavilion angles, but perhaps it works nonetheless. To my knowledge, the ideal range for larger stones is no different from that of smaller stones.

Demelza,


Although I understand the new AGS0 includes elements that are effectively ''non-calcuable,'' as for example, measures of light performance that could include direct observation, only possible with the diamond in hand...neverthess...to the extent that revised angles are iterated, I understand these angles are essentially presented and overlaid visually, when you run the HCA now, here. Since you can see how this stones parameters are outside the box, with the box intending to represent what the ostensible parameters are...perhaps you can ask your trusted vendor to account for the specific difference. As they say, the devil''s in the details. It''s best to both trust, and verify.


Regards,

I wasn''t suggesting she just trust the vendor blindly. I was just asking whether the vendor had seen the stone and whether she would be able to view the stone herself. If she does trust the vendor and he/she thinks it''s a stone worth seeing, I was suggesting that it might be worth a look either to confirm or reject the vendor''s conclusion rather than eliminating the stone based on numbers alone. Especially since it''s very hard these days to find stones in this size range.

My bad....sorry...bad hand eye coordination. I intended to address only the original poster.

Regards,

 

[Demelza]

No worries

 

[valeria101]

Date: 10/11/2005 9:26:03 AM
Author:KristyDarling


It almost seems like the definition of ideal changes depending on whom you ask!

It does

just take your pick... they are not too different.

Any chance for an IdealScope picture? That one is supposed to sort out HCA results, as much as I can tell.

 

[KristyDarling]

Thanks, Demelza and Ira! If AGS has tightened their standards, then why is this stone still considered ideal...given the big angles??? Con-fu-sion!!

I''m going to ask the vendor if they can run an ASET report as well. I''m starting to realize through this process of hunting and searching that in the end, it''s all about the stone''s light performance. Ideal numbers would be wonderful, but I''ll have to remain open-minded if I''m going to get the diamond quality and size that I want. If this stone pans out, then I will probably have it shippped here to the SF Bay Area for appraisal by Nancy Stacy.

 

[KristyDarling]

Hi Ana,

We must have hit "post" at the same time!

Yes, as soon as the diamond arrives at the vendor''s office, he said he''d do a Sarin and Idealscope. I''ll be sure to pay special attention to the idealscope. I''m also going to ask for any additional reports, such as ASET, to help me decide whether to have it shipped out here for appraisal.

 

[belle]

looking at the numbers, there doesn''t seem to be anything keeping it from being ags0, even under the new standards. i''m wondering why this stone is not hitting in the ags0 box on the hca.

 

[KristyDarling]

Hi Belle -- I just spoke with the vendor and he told me that under the new AGS0 standards, it will no longer be considered ideal...unfortunately, it is "just outside of the range."

No wonder the price was so attractive!

So, I''ve basically ruled out this stone. I am bummed, I was excited by the extra .22 carats of weight since I was originally hoping for a 3ct! I guess you can call me a size queen.

 

[Regular Guy]

Belle,

What are you referencing to represent AGS'' new standards?

 

[belle]

rg,
i thought perhaps the current version of dc included the new ags standards, but as kristydarling just confirmed, it does not.

 

[Lynn B]

Date: 10/11/2005 12:55:06 PM
Author: KristyDarling
Hi Belle -- I just spoke with the vendor and he told me that under the new AGS0 standards, it will no longer be considered ideal...unfortunately, it is ''just outside of the range.''


No wonder the price was so attractive!


So, I''ve basically ruled out this stone. I am bummed, I was excited by the extra .22 carats of weight since I was originally hoping for a 3ct! I guess you can call me a size queen.

Here''s my humble 2 cents. Since the price is "attractive", why not at least LOOK at the diamond?! I bet it is a killer stone!

And the size is TO DIE FOR!

Sometimes we get so focused on numbers around here that I think we pass by some gorgeous stones. Just a thought.

 

[KristyDarling]

Hi Lynn - you have a good point! Thing is, I guess I''m one of those people who just has to have the ideal numbers in addition to the sparkle...this stone will not be upgraded (hubby has made that abundantly clear!) and I''d like to be 100% happy about what we buy. If I buy an almost-ideal, I might continually question my decision and it''ll just bug me forever!!

It''s all Pricescope''s fault...now I know too much!

 

[Garry H (Cut Nut)]

I doubt very much that stone would get AGS 1 even.
It is on the edge of an AGS 2 / 4 range on their "candidate" chart.
GIA will give it Excellent though - so it is just a matter of opinion.

 

[KristyDarling]

THanks, Garry!

 

[Dancing Fire]

Date: 10/11/2005 12:50:14 PM
Author: belle
looking at the numbers, there doesn''t seem to be anything keeping it from being ags0, even under the new standards. i''m wondering why this stone is not hitting in the ags0 box on the hca.

i think they kick out teh old steep/deep stones in the new ags 0 system ?

 

[Mara]

Just because a stone is an AGS0 does not mean that it will score well on the HCA...I have run stones in the past that got AGS0 and scored horribly on the HCA. Not sure about old vs new standards but the HCA is penalizing for steep crown and pav angle with that table and depth.

You can also play around on the HCA to see what it DOES like. aka if that stone had same table and depth and crown angle of 34.7 and pav angle of 40.8 it would score under 2.0 with more EX's.