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Is this a nailhead?

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scarlet16

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Garry H, Leonid, David Atlas (I''ve seen your previous posts on this topic; and David I know you''re currently looking for some samples) & anyone else who can help. Can anyone tell me if this is a "nailhead"?
7.gif


Carat: .082
Color: D
Clarity: VS1
Table depth: 61.6%
Table size: 58%
Crown angle/height: 30.6/12.5%
Pavilion angle/depth: 42.4/45.5%
Culet: none
Girdle: Thin to medium

Also, when I''m asking to see more stones what should I give her as the "ideal" specs (or range) for depth, table, pavillion, crown? Thanks!
 

aphisiglovessae

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Does the diamond look like this?? I'm not very familiar with nailhead diamonds, but the GIA website says that they are "RBC diamonds with pavilions so deep that their tables look dark".

I think that the pavilion depth on that diamond might be a bit deep.





491.jpg
 

scarlet16

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Nope, from the top down it still looks very white, but then again I didn''t have it under high magnification just from my eye...
 

pricescope

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No nailhead on this DiamCalc simulation for these numbers. The diamond should be very bright but maby lacking of contrast.

ThreImNNoNeilHead.jpg
 

aphisiglovessae

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I''m not sure, but I think if it is a nailhead, you would still be able to see that dark center with your naked eye. That diamond might be just fine.
 

RockDoc

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Date: 3/17/2006 4:02:36 PM
Author: aphisiglovessae

Does the diamond look like this?? I''m not very familiar with nailhead diamonds, but the GIA website says that they are ''RBC diamonds with pavilions so deep that their tables look dark''.

I think that the pavilion depth on that diamond might be a bit deep.





The diamond in your photos has a table size of about 62%+

The first posting on this thread has the proportions of a stone with a significatntly shallow crown angle, and an overly deep pavilion.

The girdle thickness here is important to know too. My GUESS is that it is very thin or very thick.

It might not be an "official" nailhead due to the 58% table, but certainly not the cat''s meow of cutting proportions.

Rockdoc
 

scarlet16

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Rockdoc-
Thanks! What should I ask to see if I''d like "the cat''s meow" in your words? Is there a chart with the true ideal numbers for pavillion, crown and table (or at least what range I should ask for)? I think I''ve seen the "cut chart" somewhere on here but I''m not sure where.
 

chrono

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This old chart might come in handy. Just look for "round" under the tab selection. I am sure there is a newer one somewhere around here. Another useful tool that I really like to use for rounds is the HCA calculator. I'm going to look for it now. This nifty calculator crunches the numbers you put in and spits out the results.
11.gif


Edited to add:
Found it here: Holloway Cut Advisor
 

pricescope

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couple of charts from here: http://www.gemology.ru/cut/english/comp/_kozibe.htm

53.gif

Figure 1. "Kozibe", FishEye, Nail Head and Light Return plots for Table Size=53%.

* The Nail Head Effect was computed for the next parameters : Head Diameter = 15 cm (5.9"), View Distance = 40 cm (15.7").


60.gif

Figure 2. "Kozibe", FishEye, Nail Head and Light Return plots for Table Size=60%.

* The Nail Head Effect was computed for the next parameters : Head Diameter = 15 cm (5.9"), View Distance = 40 cm (15.7").
 

WinkHPD

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Date: 3/17/2006 3:10:38 PM
Author:scarlet16
Garry H, Leonid, David Atlas (I''ve seen your previous posts on this topic; and David I know you''re currently looking for some samples) & anyone else who can help. Can anyone tell me if this is a ''nailhead''?
7.gif


Carat: .082
Color: D
Clarity: VS1
Table depth: 61.6%
Table size: 58%
Crown angle/height: 30.6/12.5%
Pavilion angle/depth: 42.4/45.5%
Culet: none
Girdle: Thin to medium

Also, when I''m asking to see more stones what should I give her as the ''ideal'' specs (or range) for depth, table, pavillion, crown? Thanks!
Using Diamcalc I come up with the following pictures. As you can see the diamond is NOT a nailhead and in fact has very good light return and qualifies as an AGS 4 for light return. This first picture is as it might look in an office environment.

Wink

Is this a nailhead office.jpg
 

WinkHPD

Ideal_Rock
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This second is the ASET photo. (as created by diamcalc)

Is this a nailhead ASET.jpg
 

WinkHPD

Ideal_Rock
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And this last photo is as it might look under the IdealScope as created by Diamcalc.

While deeper than I would prefer the diamond actually should look good, but could look better in my opinion.

Wink (who will now go see what the rest of the community had to say as I have only read your first post so far...)

Is this a nailhead IS.jpg
 

WinkHPD

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And it appears I should have read further before going to play with my new Diamcalc software. Leonid not only already did the work, but knows how to put all of these in one post.

As Leonid has correctly said the stone is lacking in a good contrast pattern with most of the contrast and the leakage lumped in the cirle that is beginning to form the "ring of death". It is not there yet, but quickly approaching.

It should be an attractive stone, but could be better in my opinion.

Wink
 

scarlet16

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Thanks so much for all your help!
 
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