What about this diamond? GIA-Excellent but AGA-1B

[esp102]

I found a diamond but I''m only going by it''s cert Graded Execllent cut by the GIA but I ran it through the AGA online program. The only thing that hurts me is the Pavilion Depth % of 44.0%

Suggestions on if I can do "better" or take the diamond?

This is so difficult because most buyers don''t have the luxury to review several diamonds at once. We can only go by what''s on the paper but I don''t want to pass on a great diamond.

Would a better Pavilion Depth % be noticeable?

Where can I find the AGS-0 cut rules?


Shape: Round

Table % 57.0% Grade: 1A
Crown Angle 34.0° Grade: 1A
Crown Height % 14.5% Grade: 1A
Pavilion Depth % 44.0% Grade: 2A
Girdle Thickness Thin to Medium Grade: 1A
Total Depth % 60.80% Grade: 1A
Polish Excellent / Very Good Grade: 1A * Not a primary determining factor.
Symmetry Excellent / Very Good Grade: 1A * Not a primary determining factor.

Final Grade: 1B

 

[belle]

i see the polish and symmetry are graded excellent but are you sure the ''cut grade'' is excellent?

 

[esp102]

GIA-Excellent Cut Grade.

 

[Capitol Bill]

Hi esp102,

Looks like you''ve been doing lots of homework. And you appear to have great organizational skills. But one of the most crucial pieces of information is missing -- pavilion angle. Without it you''re flying blind. When you get the pavilion angle, try plugging the numbers into the HCA and see what you come up with. And don''t get so caught up in the numbers that you forget that the most important step is in the actual viewing of the stone. Regardless of what the numbers say, the stone still should "speak" to your particular taste.

Best of luck!
Bill Scherlag

 

[esp102]

Hi,

pavilion angle = 41.2

 

[JulieN]

2.9 HCA

 

[esp102]

After researching this diamond, I think it''s a perfect example of why cutters send diamonds to certain cert companies.

If AGS, it looked like it would be graded an AGS-1 for cut.

But GIA graded it Excellent for Cut.

 

[MissGotRocks]

If the pav angle was 40.9 instead of 41.2 would it be an AGS0 under their new guidelines?

 

[Garry H (Cut Nut)]

Date: 4/26/2006 11:16:45 PM
Author: esp102
Hi,

pavilion angle = 41.2

Rounded data - 41.1 would be OK
41.3 would be lousy

 

[esp102]

Here is the Sarin Report for this stone.

Notice how the results are all AGS-0.

Can the diamond be adjusted in the Sarin to give AGS-0 results? Are they accurate?

 

[Paul-Antwerp]

The summarized Sarin-report, which you have there, bases its AGS-grade on the old AGS-system.

The big variations within each and every angle bother me. The GIA-system does not pick up these variations, nor did the old AGS-system. The new AGS-system works with a full 3D-scan of the stone, and will pick up the effect of these variations.

Because of this, the average angles might indicate that the stone could get an AGS-1 grade, but with these variations, I doubt whether this will be the case.

Live long,

 

[Garry H (Cut Nut)]

As Paul said - The old aGS system acepted steeper and deeper proportions - almost as steep deep as the new GIA system.
But AGS found when they moved to light performance that those proportins did not quite make the best looking stones.

It will not be a bad stone - but I would not buy it for my store.

The variation need not be a problem - I have seen H&A''s stones with as much variation - it depends on the alignment of the C/P facets - sometimes it is simply a tilted table causing the C/P to vary