Is my princess cut cut too deep?

[DON HULIO]

I posted a question before, however, it was apparently posted in the wrong forum. Sorry, I''m new to this. So, I will re-post my question. With regard to the matter of dept in a princess cut, is my diamond cut too deep, and based on the following, is it a good cut?

Shape and cutting style: Rectangular Modified Brilliant
Measurements: 5.53 x 5.23 x 3.93mm
Weight 1.01 carat
Proportions:
Depth: 75.1 %
Table: 77.0%
Girdle: Medium to Extremely Thick
Cutlet: none

Finish:
Polish: Very Good
Symmetry: Good
Clarity Grade: VS2
Color Grade: D
Fluorescence: Faint

Any feedback is appreciated, thanks again!

Don Hulio

 

[researcher]

Honestly, it''s too hard to tell. I was told not to go for stones with a depth greater than 75%, so I wouldn''t say your stone is horribly deep (but it IS on the deep side which can make the stone look small for it''s size). Also, you really don''t want to have a girdle that varies so much, nor one that is extremely deep (it means your stone holds a lot of its weight in a place no one will see it, so the stone will look small). Also, the best stones tend to have a table that is equal to or less than the depth. The relationship between the table and the depth somewhat predict the crown height which is responsible for the fire of your stone. With such a large table (yours is outside of the premium specs) your stone most likely lacks the fire of other stones. Overall the numbers suggest a stone that might have leakage problems and most likely isn''t a high performer. That being said, there are always exceptions. Do you have a Sarin report or other report that offers the crown and pavilion %''s and angles? Do you have an ideal scope image? Just so you can get an idea of the size you''ve lost due to the depth and girdle, a standard 1 ct princess cut stone should measure about 5.6x5.6mm whereas your stone measures 5.5x5.2mm. It''s not a huge difference, but I''ve heard the human eye notices differences in size at the rate of .10mm.

I hope this helps!

 

[Paul-Antwerp]

Depth as such, in a princess-cut, has no effect on the light performance or the spread of the stone. As such, depth is not important. I now have 2 stones returning from AGS with the new AGS-0-grade, and their depth is higher than 80%. Despite this very high depth, they have great light performance and spread. Therefore, depth means nothing.

What is important, are the areas where a cutter can hide weight. I have mentioned the ''pavilion 1'' before, and another well-known area is the girdle.

In your case, because of the diameters of your stone being rather low, it is clear that a lot of weight is hidden in the girdle and in that P1-angle. In your report, you can only see it in the mentioning of the Extremely Thick girdle.

The conclusion therefore is: your princess is not too deep, but she is definitely hiding weight in the girdle and in the P1. Therefore, she has unsufficient surface.

Live long,

 

[researcher]

Paul,
I guess I''m still confused regarding your article on depth (my questions were never really answered in the other thread). I was under the understanding that, while the depth itself may not have an effect on light performance or the spread of the stone, the combination of the table and depth (along with pavilion and crown angles) provides insight into the performance of the stone. Is this not accurate? Why is it that the deeper stones with larger tables tend to leak light (at least in my experience)? I''m just curious and don''t really understand what people look for in princesses today (what are the parameters of the AGS-0-grade?). Any insight you can provide would be greatly appreciated!!!

 

[DON HULIO]

Thank you all for the feedback. I have not seen the stone, but have just purchased it...maybe this was a mistake. The jeweler that I purchased it from told me that it would appear slightly smaller, more like a .9 to a .95 carat. I understood this, but I was attracted to the D color and the VS2 clarity. When I purchased it I did not realize all of the things that you all posted, like where carat weight is hidden, etc. The jeweler assured me that aside from the size/apperance factor that this was a great looking stone, with good scintilation and fire... Thus, aside from the apperance of a smaller than 1.01 carat stone, is it still a worth while stone for US $4000, or have I paid too much and should I have continued my search? Thanks again for any feedback.

 

[DON HULIO]

Date: 4/25/2005 3:46:12 PM
Author: Paul-Antwerp
Depth as such, in a princess-cut, has no effect on the light performance or the spread of the stone. As such, depth is not important. I now have 2 stones returning from AGS with the new AGS-0-grade, and their depth is higher than 80%. Despite this very high depth, they have great light performance and spread. Therefore, depth means nothing.

What is important, are the areas where a cutter can hide weight. I have mentioned the ''pavilion 1'' before, and another well-known area is the girdle.

In your case, because of the diameters of your stone being rather low, it is clear that a lot of weight is hidden in the girdle and in that P1-angle. In your report, you can only see it in the mentioning of the Extremely Thick girdle.

The conclusion therefore is: your princess is not too deep, but she is definitely hiding weight in the girdle and in the P1. Therefore, she has unsufficient surface.

Live long,

Paul, I read your article, and it was very informative. Thanks. I guess I''m feeling a little bit nervous about my princess cut now based on the responses that I''ve received. Insufficient surface just means a smaller top view, correct? This does not mean poor light reflection, scintilation, fire, etc does it? The other diamond that I narrowed it down to was a .9 carat E, SI1 round brilliant. Unfortunately, I do not have the specs in front of me, but could this have been a better choice? I was excited about the princess cut because it is a D (best color grade and one grade higher than the round), VS2 (Higher clarity grade than the round), 1.01 carat (10 points more of diamond weight than the round), for and extra $150.00. In other words, the round brilliant was $3950 mounted, the princess cut is $4100 mounted. I now realize that cut has a lot to do with the quality of the diamond. I got three out of the four C''s, anyway. I realize that you prefer not to comment on prices and values, but please respond if for no other reason than to confirm my nervousness or dispell my fears that I may have made the wrong choice in selecting the princess cut for my soon to be engaged girlfriends hand. I''ve read some posts about picky individuals that are never satisfied (I could be one of those people), and I realize that this is supposed to be a special and enjoyable process, so am I being too picky? I guess I''ll know for sure when I view my princess cut for the first time.

Thanks again!

 

[Paul-Antwerp]

Date: 4/25/2005 3:46:12 PM
Author: Paul-Antwerp
I now have 2 stones returning from AGS with the new AGS-0-grade, and their depth is higher than 80%.

I am sorry, but when I wrote this, I did not have the exact data with me. Checking today, their depth is 77%.

Sorry about that,

 

[Paul-Antwerp]

Date: 4/25/2005 9:25:30 PM
Author: crankydave

Date: 4/25/2005 3:46:12 PM
Author: Paul-Antwerp

The conclusion therefore is: your princess is not too deep, but she is definitely hiding weight in the girdle and in the P1. Therefore, she has unsufficient surface.

Paul,

What? Wouldn''t more surface mean less depth and visa-versa on equal weight stones?

Dave

Indeed, Dave, it does not mean that.

Depth consists of three parts, crown height, girdle thickness and pavilion depth.

One way to decrease surface without necessarily adding depth, is by increasing the girdle thickness, and working with lower crown height and pavilion depth. In this way, one adds weight at the thickest part, while giving up a little bit of weight in the less thicker part. The result is that one has less surface with the same depth. But one simple glance at the girdle thickness immediately shows this phenomenon.

In rounds, one can slightly play with the crown area (keeping the same height, but minimizing surface), but this is minimal. In the pavilion area however, pavilion depth is directly related to the main pavilion angle, and there is a direct relation between the depth and the surface.

One cannot use this rule of rounds for princess-cuts however. The pavilion of a princess-cut has two main pavilion angles (P1 and P2). P2 goes from culet to girdle and thus dictates the pavilion depth. P1 however, is totally independent from P2, and has no relationship with the pavilion depth. This is an area where one can add a lot of weight without touching the depth.

In this thread (examples), I have shown examples of 2 stones having the same weight, the same surface, and one having a depth of 75% and the other one of 65%. At the same time, there is an example, where I adapt only the P1-angle (equal depth, table, and other angles) and in this way can turn the stone from an AGS-5 into an AGS-0.

The whole concept of depth not being related to surface sounds illogical to most people, and therefore, I keep on stressing it. It is extremely important to understand this.

Live long,

 

[valeria101]

Date: 4/25/2005 8:41:16 PM
Author: DON HULIO

aside from the apperance of a smaller than 1.01 carat stone, is it still a worth while stone for US $4000, or have I paid too much and should I have continued my search?

The size and price appear to be very much in line - both fit a .9carat princess. If the stone looks good (= brilliant), I can''t see any good reason to look further. Perhaps most 1 carat princess cuts are a bit larger, but not by all that much.