Great deal, or am I missing something?

[newdave]

Hi all,

I''m a long-time lurker on PS and have amassed a wealth of info from all you great posters, but now I have my own newbie question for you about a diamond I am seeing soon. It''s a round brilliant, F SI1, 1.00 carat for $4100 at a B&M. Here are all the specs I could think to get...

1. Depth 62.8%

2. Table 56%

3. Crown 16%

4.Pavilion 44%

5. Cutlet None

6. Girdle Thin to Med, Faceted

7. Certificate cut rating Tolkowsky Ideal Cut

8. Fluorescence None

9. Polish Excellent

10. Symmetry Very Good

The HCA analysis didn''t seem to loveit, and I''m not crazy about VG symmetry (vs. excellent), but I still feel that this is a fantastic price.

-What could I be missing besides some horrible inclusion?
-Is there anything in particular I should look for when I go and see it in a few days?
-I also don''t know what the "Tolkowski Ideal Cut" is. Is that at odds with the VG symmetry?
-Is this price too good to be true, or am I just cynical now after my weeks of research? I''ve compared it to prices online and it seems underpriced.

I''m probably overthinking it, but I''m very obsessive about big purchases, and of course I want her ring to be perfect! Thanks in advance for all your help!

 

[Todd Gray]

In 1919, Marcel Tolkowsky, a member of a Belgian family of diamond cutters, published Diamond Design, the first recorded analysis of diamond proportions for the round brilliant cut diamond. His work was based on modern theories of light behavior and his opinion of what proportions resulted in what many industry professionals considered to be the best possible balance of brilliance and dispersion of light until the late 1990''s.

Tolkowsky’s calculations indicate that for optimum brilliance a round brilliant cut diamond should be cut to the following angles and proportions:

* 34.5° Crown Angle.
* 40.75° Pavilion Angles.
* 59.3% Total Depth (excluding girdle thickness) with 16.2% of the depth being comprised of the crown (top half of the diamond) and 43.1% representing the pavilion lower half of the diamond.
* 53% Table based on diamond''s overall diameter.

Tolkowsky''s design is frequently referred to as the "American Ideal Cut" because diamond cutters in the United States began cutting it first. Marcel Tolkowsky''s early model of brilliance set the stage for the modern AGS Ideal Cut Diamond and Hearts & Arrows Ideal Cut Diamond which are the most brilliant and dispersive diamonds available on the open market today.

Do not be confused or misled by the appearance of the words "Tolkowsky Cut" on some diamond grading reports. The words "Tolkowsky Cut" do not necessarily mean that a diamond has been cut to Tolkowsky''s exact specifications. Some laboratories will say that a diamond is "Tolkowsky Cut" or within "Tolkowsky Range" if the diamond''s proportions are "within tolerance" of Tolkowsky''s original calculations. According to the specifications of one laboratory, "Tolkowsky Range" is as follows:

* 33 - 36° Crown Angle.
* 40 - 41.5° Pavilion Angles.
* 56 - 60.5% Total Depth (excluding girdle thickness) with 14 - 16.5% of the depth being comprised of the crown (top half of the diamond) and 42 - 44% representing the pavilion lower half of the diamond.
* 53 - 57% Table based on diamond''s overall diameter.

 

[jet2ks]

Well, it''s pretty deep for one, which most likely means it is not a top performer. Also, is this an EGL cert, and if so, which branch (USA, Israel or Europe)?

 

[John P]

Hi NewDave,

Value depends on a number of factors, some more significant than others. A big one is knowing what lab graded the diamond. You''ve posted F SI1 but grading standards are not uniform. If the lab was not strict it could possibly be a G SI2, or lower, when held to strictest standards.

The major proportions you provided correspond to crown and pavilion angles of 36.0/41.4. This is not the best combination for light return; a notable amount of light at these angles is not returned to the eye, making it less bright than the best performing rounds in many lighting conditions. The 62.8% depth makes it face up a tiny bit smaller than 1ct diamonds which have optimum spread, but not too badly.

To answer the question about price it''s important to know the lab which graded the diamond and how much importance you place on cut as opposed to the other Cs.

 

[John P]

Hi Todd and Jet - we were posting at the same time.

 

[jet2ks]

Date: 7/16/2009 12:36:45 AM
Author: John Pollard
Hi Todd and Jet - we were posting at the same time.

Hi, John. Great minds, you know.

Yeah, two experts and me. (Cue Sesame Street "One of these is not like the other . . . . ")

 

[John P]

Date: 7/16/2009 12:45:21 AM
Author: jet2ks

Great minds, you know.

Yeah, two experts and me. I kinda think one doesn''t seem to belong.

...just as I was thinking "Hey. Jet pointed out what Todd & I did in only 2 sentences."

 

[Dancing Fire]

Date: 7/16/2009 12:32:29 AM
Author: jet2ks
Well, it''s pretty deep for one, which most likely means it is not a top performer. Also, is this an EGL cert, and if so, which branch (USA, Israel or Europe)?

yep,most likely if the report say...Tolkowsky Ideal Cut.

 

[newdave]

Thanks for the responses. The cert is EGL, but not sure which branch. Which is the most "trustworthy", so to speak, in terms of strictness in grading?

Thanks for the info Todd. I had heard of Tolkowsky, but never specifically of "Tolkowsky Ideal cut" so I didn't know if that was some sort of standard I had never heard of.

And John and Jet, thank you for pointing out the depth. I have seen two identical carat weights with different depths side by side before, and I now remember the unflattering difference I saw in the one that was cut too deep. It looked a lot smaller and not as brilliant.

Cut is probably most important to me, as I really want the best light return I can get. Next in importance I think would be the color. This diamond is about $1K under my tentative budget, but I'm gonna take a look at it tomorrow morning just to get a sense of it. I've only just started looking seriously at B&M stores, and I'm surprised to find that I actually feel more comfortable and informed when I'm looking at online vendors. I may just go that way after all. Thanks for the input! I'll let you know how it looks.

 

[Lorelei]

Date: 7/16/2009 12:48:06 AM
Author: John Pollard

Date: 7/16/2009 12:45:21 AM
Author: jet2ks

Great minds, you know.

Yeah, two experts and me. I kinda think one doesn''t seem to belong.

...just as I was thinking ''Hey. Jet pointed out what Todd & I did in only 2 sentences.''

Jet is good.....

 

[jet2ks]

Date: 7/16/2009 1:52:01 AM
Author: newdave
Thanks for the responses. The cert is EGL, but not sure which branch. Which is the most 'trustworthy', so to speak, in terms of strictness in grading?

Thanks for the info Todd. I had heard of Tolkowsky, but never specifically of 'Tolkowsky Ideal cut' so I didn't know if that was some sort of standard I had never heard of.

EGL-USA is considered the most strict of those three, though not quite as strict as GIA or AGS. A stone graded by EGL-Israel or EGL-Europe can sometimes be two grades off in color and/or clarity compared to how GIA or AGS would grade the same stone, so this could easily be similar to a GIA H SI2 (or it might be accurately graded). If it is EGL-USA, it will say on the top of the report.

And John and Jet, thank you for pointing out the depth. I have seen two identical carat weights with different depths side by side before, and I now remember the unflattering difference I saw in the one that was cut too deep. It looked a lot smaller and not as brilliant.

Cut is probably most important to me, as I really want the best light return I can get. Next in importance I think would be the color. This diamond is about $1K under my tentative budget, but I'm gonna take a look at it tomorrow morning just to get a sense of it. I've only just started looking seriously at B&M stores, and I'm surprised to find that I actually feel more comfortable and informed when I'm looking at online vendors. I may just go that way after all. Thanks for the input! I'll let you know how it looks.

Make sure when you look at the stone to get it away from the display lighting, as that is designed to make even poorly cut diamonds look good. Since you mention being more comfortable with online vendors, why not just look at some of the respected PS vendors?

(Thanks, John and Lorelei

)

 

[Ellen]

Date: 7/16/2009 4:53:08 AM
Author: Lorelei

Date: 7/16/2009 12:48:06 AM
Author: John Pollard

Date: 7/16/2009 12:45:21 AM
Author: jet2ks

Great minds, you know.

Yeah, two experts and me. I kinda think one doesn''t seem to belong.

...just as I was thinking ''Hey. Jet pointed out what Todd & I did in only 2 sentences.''

Jet is good.....

That he is.

lol at sesame street!

 

[Lorelei]

Most welcome Monsieur Le Jetskis!