Need advice on this diamond.

[akim1220]

I posted last week about a diamond that I needed advice on and I feel like I got the right advice as that diamond was considered a steep deep diamond. I told my jeweler that I will pass and he has a new diamond for me. One of the repliers (I think lorelai or something) gave me a range to stay in with the CA and PA. The new diamond falls right outside the range by 0.5 degree. I have not seen it in person yet. I would greatly appreciate it if I could get expert advice on this stone. How would you rate it from a scale between 1-5? Would you accept this stone? How lively will this be?

ROUND BRILLIANT

Measurements: 7.38 - 7.42 x 4.61 mm
Carat Weight: 1.54 carat
Color Grade: G
Clarity Grade: SI1
Cut Grade: Excellent
PROPORTIONS:

Depth: 62.3%
Table: 56%
Crown Angle: 35.5°
Crown Height: 15.5%
Pavilion Angle: 41.0°
Pavilion Depth: 43.5%
Star length: 50%
Lower Half: 75%
Girdle: Thin to Medium, Faceted (3.0%)
Culet: None
FINISH:

Polish: Excellent
Symmetry: Excellent
Fluorescence: None
Comments: Additional twinning wisps are not shown.Surface graining is not shown.

 

[stone-cold11]

Not good, leaky, pavilion angles too big for that crown angle.

 

[Lorelei]

Hi akim

Its what is called a steep deep, very often these angle combos can leak light, I would keep looking. No way to rate it properly without images but suffice to say there is a high probability of light leakage, this is typical of steep deeps.

 

[akim1220]

I just realized that the CA and PA are the same on this diamond as the one I previously posted about. If I want to stay in the $10K to $13K and still keep an F-G, VS2-SI1, and excellent cut, should I look for a smaller weight? Just went through a couple of diamonds on Bluenile and it seems like none of them have the CA and PA range or are these just that tough to find?

 

[Lorelei]

Date: 11/4/2009 2:09:52 PM
Author: akim1220
I just realized that the CA and PA are the same on this diamond as the one I previously posted about. If I want to stay in the $10K to $13K and still keep an F-G, VS2-SI1, and excellent cut, should I look for a smaller weight? Just went through a couple of diamonds on Bluenile and it seems like none of them have the CA and PA range or are these just that tough to find?

Well cut diamonds are out there akim and BN do have some for sale, it can just take a bit of work to find them and you commonly find steep deep diamonds out there when searching. Do you prefer to buy from BN or do you not mind as long as the vendor has what you are looking for?

 

[stone-cold11]

Plenty in JA. Even a H&A, for example this. http://www.jamesallen.com/diamonds/F-SI1-Ideal-Cut-Round-Diamond-1239032.asp

The largest I found in your specs and price range. http://www.jamesallen.com/diamonds/G-SI1-Ideal-Cut-Round-Diamond-1268161.asp

Note, I haven't look at the images, only by the numbers for these stones.

 

[akim1220]

Date: 11/4/2009 2:20:08 PM
Author: Lorelei

Date: 11/4/2009 2:09:52 PM

Well cut diamonds are out there akim and BN do have some for sale, it can just take a bit of work to find them and you commonly find steep deep diamonds out there when searching. Do you prefer to buy from BN or do you not mind as long as the vendor has what you are looking for?

I was just using BN as a reference. I would like to stay with my jeweler, if I ever want to return or upgrade the diamond he will give me a 100%. And also he is giving me a discount which would be equivalent to the sales tax.

 

[akim1220]

Date: 11/4/2009 2:23:09 PM
Author: Stone-cold11
Plenty in JA. Even a H&A, for example this. http://www.jamesallen.com/diamonds/F-SI1-Ideal-Cut-Round-Diamond-1239032.asp


The largest I found in your specs and price range. http://www.jamesallen.com/diamonds/G-SI1-Ideal-Cut-Round-Diamond-1268161.asp


Note, I haven''t look at the images, only by the numbers for these stones.

Thanks for the examples. That 2nd diamond you have linked has a CA of 35.5 and a PA of 40.6. Is it better to have a higher CA than a PA and vice versa? The steep deep daimonds that I was seeking advice for has a 35.5 CA and a 41 PA, so I am assuming that a steep deep diamond is one that has a high CA and a high PA.

 

[stone-cold11]

yap, high crown angle is complemented with a shallow pavilion angle and vice versa.

 

[Lorelei]

Date: 11/4/2009 2:38:03 PM
Author: akim1220

Date: 11/4/2009 2:20:08 PM
Author: Lorelei

Date: 11/4/2009 2:09:52 PM

Well cut diamonds are out there akim and BN do have some for sale, it can just take a bit of work to find them and you commonly find steep deep diamonds out there when searching. Do you prefer to buy from BN or do you not mind as long as the vendor has what you are looking for?

I was just using BN as a reference. I would like to stay with my jeweler, if I ever want to return or upgrade the diamond he will give me a 100%. And also he is giving me a discount which would be equivalent to the sales tax.

Ok I understand. Ask your jeweller if he can source you some AGS0 cut grade and some GIA Excellent, you could narrow the angles down as follows if it makes it a bit easier for you.

Crown angles keep within 34 deg and 35 deg, pavilion 40.6 - 40.8 This is a pretty tight range but will narrow things down considerably.

Alternatively use the numbers on the cheat sheet I gave you and run each diamond through the Holloway Cut Advisor and look for those which score between 1 and 2 initially. And of course you can always report back here for advice.

 

[Lorelei]

Date: 11/4/2009 2:41:04 PM
Author: akim1220

Date: 11/4/2009 2:23:09 PM
Author: Stone-cold11
Plenty in JA. Even a H&A, for example this. http://www.jamesallen.com/diamonds/F-SI1-Ideal-Cut-Round-Diamond-1239032.asp


The largest I found in your specs and price range. http://www.jamesallen.com/diamonds/G-SI1-Ideal-Cut-Round-Diamond-1268161.asp


Note, I haven't look at the images, only by the numbers for these stones.

Thanks for the examples. That 2nd diamond you have linked has a CA of 35.5 and a PA of 40.6. Is it better to have a higher CA than a PA and vice versa? The steep deep daimonds that I was seeking advice for has a 35.5 CA and a 41 PA, so I am assuming that a steep deep diamond is one that has a high CA and a high PA.

There is a lot more flexibility with crown angles than pavilion angles, therefore it can be preferable to have a steeper or shallower crown angle than to have much variance with the pavilion. As an example, although crown and pavilion angles can balance each other out, once you start getting a pavilion angle which gets much over 41 degrees you can find various undesirable issues develop such as colour entrapment in some cases and light leakage, so try to keep pavilion angles generally between 40.6 and 41 degrees.

A steep deep is a diamond that has crown and pavilion angles which are too steep and deep respectively to work well together, hence the term steep deep.