Please help me understand how bad my diamond''s cut is.

[FancyDiamond]

I wish to be able to relate the appearance of a diamond in real life to its statistics on paper. I have seen lots of examples of top cut grade diamonds from pricescope and my recent diampnd purchase. However, I do not know enough about an average cut (e.g., GIA good cut grade) diamond. The stone in my old ering has an old GIA certificate which does not tell much about the diamond''s performance. All I know is that in real life the stone has acceptable though not great sparkles and fair contrast (the center looks cloudy). I would love to understand how bad the cut is. Your help is much apprecited.

Please comment on the cut of my diamond in terms of
light return, fire, scintillation, contrast, and anything I need to know.

Here is the info on my diamond.
Depth 58.1%
Table 60.2%
crown 31.4 degrees, 12.3%
Paviion 41.2 degrees, 43.7%
girdle min 0.4%, very thin
girdle maximum 1.3% medium
star/upper ratio 55:45
Lower girdle halves 82%
HCA = 2.0 VG light return, VG fire, G scintillation, and EX spread (Somehow, I think these predictions are much better than reality, as shown by ASET.)

ASET is attached.

 

[John P]

Date: 8/12/2009 3:09:27 PM
Author:FancyDiamond
I wish to be able to relate the appearance of a diamond in real life to its statistics on paper. I have seen lots of examples of top cut grade diamonds from pricescope and my recent diampnd purchase. However, I do not know enough about an average cut (e.g., GIA good cut grade) diamond. The stone in my old ering has an old GIA certificate which does not tell much about the diamond's performance. All I know is that in real life the stone has acceptable though not great sparkles and fair contrast (the center looks cloudy). I would love to understand how bad the cut is. Your help is much apprecited.

Please comment on the cut of my diamond in terms of
light return, fire, scintillation, contrast, and anything I need to know.

Here is the info on my diamond.
Depth 58.1%
Table 60.2%
crown 31.4 degrees, 12.3%
Paviion 41.2 degrees, 43.7%
girdle min 0.4%, very thin
girdle maximum 1.3% medium
star/upper ratio 55:45
Lower girdle halves 82%
HCA = 2.0 VG light return, VG fire, G scintillation, and EX spread (Somehow, I think these predictions are much better than reality, as shown by ASET.)

ASET is attached.

Nice brightness in the ASET. However what you report is not surprising - hold it close, then move it away and you will probably note that it gets brighter as you increase the distance from your nose. It's a shallow configuration, which means that the shadow your head casts (or any observer) will be reflected more than normal as you move it close to your face. In HCA terms it would be better as a pendant or earring diamond for these reasons. At normal & close viewing distances it will tend to go dark.

 

[FancyDiamond]

Date: 8/12/2009 4:02:07 PM
Author: John Pollard

Date: 8/12/2009 3:09:27 PM
Author:FancyDiamond
I wish to be able to relate the appearance of a diamond in real life to its statistics on paper. I have seen lots of examples of top cut grade diamonds from pricescope and my recent diampnd purchase. However, I do not know enough about an average cut (e.g., GIA good cut grade) diamond. The stone in my old ering has an old GIA certificate which does not tell much about the diamond''s performance. All I know is that in real life the stone has acceptable though not great sparkles and fair contrast (the center looks cloudy). I would love to understand how bad the cut is. Your help is much apprecited.

Please comment on the cut of my diamond in terms of
light return, fire, scintillation, contrast, and anything I need to know.

Here is the info on my diamond.
Depth 58.1%
Table 60.2%
crown 31.4 degrees, 12.3%
Paviion 41.2 degrees, 43.7%
girdle min 0.4%, very thin
girdle maximum 1.3% medium
star/upper ratio 55:45
Lower girdle halves 82%
HCA = 2.0 VG light return, VG fire, G scintillation, and EX spread (Somehow, I think these predictions are much better than reality, as shown by ASET.)

ASET is attached.

Nice brightness in the ASET. However what you report is not surprising - hold it close, then move it away and you will probably note that it gets brighter as you increase the distance from your nose. It''s a shallow configuration, which means that the shadow your head casts (or any observer) will be reflected more than normal as you move it close to your face. In HCA terms it would be better as a pendant or earring diamond for these reasons. At normal & close viewing distances it will tend to go dark.

Ah! I understand now. Your explanation imakes a lot of sense. Thank you very much for your informative and clear explanation.

I am planning to have the stone recut to near ideal perfection and set it in a pendant. Now with your explanation, I wonder if recut is a wrong move. I worry more about losing size (diameter more so than weight) than the cost of recut. I was hoping that recut can help both the overal light performace and contrast. Do you think that recut is a bad decision?

 

[John P]

You're welcome. Glad to help.

In any recut situation the diamond would need to be seen by an expert, but with the shallow parameters you absolutely stand to lose quite a bit and it may prove tricky with the girdle running to VT. If you intend it as a pendant stone anyway perhaps you can find some diamonds that look great to you and compare yours side-by-side in different lighting conditions from about 24" away. It's not likely to have as much fire as a diamond of near-Tolk make, if that's your comparison, but it could be very bright and attractive at that distance.

 

[Rockdiamond]

Fancydiamond: there is a question I have.
You mention the diamond looks cloudy in the center. That is generally not something attributable from the cut. Certainly the stats of your stone don''t indicate anything what would cause cloudiness.
I''m wondering if there are other aspects coming into play here.
What are the GIA color and clarity?

 

[John P]

Date: 8/12/2009 5:14:23 PM
Author: Rockdiamond
Fancydiamond: there is a question I have.
You mention the diamond looks cloudy in the center. That is generally not something attributable from the cut. Certainly the stats of your stone don't indicate anything what would cause cloudiness.
I'm wondering if there are other aspects coming into play here.
What are the GIA color and clarity?

In my experience consumers sometimes use "cloudy" to describe table reflection in some lighting - as opposed to the trade where we automatically connect the term to clarity or overfluorescence.

>

In this case I interpreted cloudy as table reflection. It would make sense given the combo and especially when seeing TR show as blue in the ASET: The areas circled below show how table reflection impacts the stated parameters in a perfect wireframe simulation (L) and how the actual diamond has a larger, asymmetric area of table reflection caused by its cut particulars (R).

Fancy, if you're seeing something other than this let me know.

 

[Rockdiamond]

Great point John!
Interesting possibility about the differences in interpretation of the word cloudy.
No question there are many such cases- where a term is used that has relevance- but means something different to separate listeners.
I also am interested in Fancydiamond''s impression!

 

[FancyDiamond]

Date: 8/12/2009 6:19:37 PM
Author: John Pollard

Date: 8/12/2009 5:14:23 PM
Author: Rockdiamond
Fancydiamond: there is a question I have.
You mention the diamond looks cloudy in the center. That is generally not something attributable from the cut. Certainly the stats of your stone don''t indicate anything what would cause cloudiness.
I''m wondering if there are other aspects coming into play here.
What are the GIA color and clarity?

In my experience consumers sometimes use ''cloudy'' to describe table reflection in some lighting - as opposed to the trade where we automatically connect the term to clarity or overfluorescence.

<< All I know is that in real life the stone has acceptable though not great sparkles and fair contrast (the center looks cloudy). >>

In this case I interpreted cloudy as table reflection. It would make sense given the combo and especially when seeing TR show as blue in the ASET: The areas circled below show how table reflection impacts the stated parameters in a perfect wireframe simulation (L) and how the actual diamond has a larger, asymmetric area of table reflection caused by its cut particulars (R).

Fancy, if you''re seeing something other than this let me know.

You are right about your interpretation. I do not know the appropriate terms to describe what I see. As you said, the stone looks great from a distance. Yet, when I take a closer look, I can''t see the center, or I can''t see through the stone there as opposed to the outer area. If I view the stone from the side, I can see the center very clearly. The stone color is F and VVS2 clarity. Can''t see any flaws even with my loupe.

Just wonder what incremental benefits (in terms of llight perfromance I can get from recut? When I place the stone side by side with my 2.383 ACA, it looks almost as great, just not as sparkling (in a grand way). The most observable difference is not being able to "see through" the center viewing closeup. The other difference is contrast, but I think it has to do with polish (good vs ideal).

 

[Rockdiamond]

HI Fancy!
My totally off the cuff impression ( I agree with John that the stone must be looked at by a cutter) is that a re-cut makes no sense.

In terms of what you are seeing, the fact the Polish was graded "Good" versus EX ( or Ideal) is NOT visible to the naked eye- so there are other factors.
All in all, it does not sound as though the stone is a big issue as you seem to also like how it looks- also going into my comment that a re-cut doesn''t seem to make sense.

 

[John P]

Date: 8/12/2009 6:50:42 PM
Author: FancyDiamond

You are right about your interpretation. I do not know the appropriate terms to describe what I see. As you said, the stone looks great from a distance. Yet, when I take a closer look, I can't see the center, or I can't see through the stone there as opposed to the outer area. If I view the stone from the side, I can see the center very clearly. The stone color is F and VVS2 clarity. Can't see any flaws even with my loupe.

Confirmed. Table reflection & obstruction caused by proximity. Sounds like a beautiful color & clarity.

Just wonder what incremental benefits (in terms of llight perfromance I can get from recut? When I place the stone side by side with my 2.383 ACA, it looks almost as great, just not as sparkling (in a grand way). The most observable difference is not being able to 'see through' the center viewing closeup. The other difference is contrast, but I think it has to do with polish (good vs ideal).

The reason you're hearing me and David warn you about a recut in this case is simple geometry: If you wanted shallower angles on a deep diamond that might be accomplished by reducing depth with no change to diameter (again it depends on the goals) so negligible loss of spread... But you have a shallow diamond and want steeper angles. You can't increase the depth, so the weight loss must occur by reducing the diameter to make the angles steeper. Basically, you're talking about significant weight/spread loss. I may have missed how big the stone is. If you don't mind a much smaller diamond that has top brightness and fire close-up you could look into it.

If this was your only diamond and you intended it for an e-ring and you really wanted a different look my advice might be different. Honestly, there are plenty of diamonds out there that don't perform well from any distance. Yours sounds nice for a pendant.

 

[FancyDiamond]

Attached photo shows how my two diamonds look like. The one on the right is the 1.12 ct in question.

I am beginning to understand that my diamond is a borderline case, and I hear your recommendation. Just to make sure more before I decide. If the recut results in a weight loss of say 10% and a diameter decrease of 5% (guess the spread and table may suffer even more), is it still worthwhile to get the recut for perfect or near perfect light performance? In other words, will the recut diamond look better from 12 inches away?

 

[Rockdiamond]

Here's my take:
If you were saying, I love the stone on e left so much, and I really am not satisfied with the one on the right- and your main purpose was only to own these- - with no concern to value, than maybe it might make sense to explore it further.
If your feelings about the 1.12 are less ....severe, and you are interested on what the value of the diamond will be afterwards, it is far less of a sure thing, , IMO

 

[LGK]

I will say that as far as pendants go, you don''t see them yourself much, so a less than perfect stone can be much more acceptable in a pendant. I have a center stone in my pendant that I would nitpick at endlessly if it was on my finger. But since it''s around my neck I''m happily oblivious, and it looks pretty enough. I''d probably just stick that sucker into a pendant and if it bugs you later get it recut then. I bet, though, once it goes around your neck you''ll realize you never see it yourself except cleaning it, and it won''t bother you anymore. That''s been my experience anyway. (Earrings even more so. I wear a pair of *seriously* crap cut studs probably cut in the ''70s- they''re decent color and clarity, and about .60ish cttw, and I paid $100ish for them. The tables are so big it''s kind of mind blowing- but since I don''t see them much, and I loved the settings, they''re fine in the 4th hole in my ears... but I''d never consider wearing them on a finger, where I''d actually have to look at those little fisheyes staring back at me!)

 

[Garry H (Cut Nut)]

Date: 8/12/2009 6:19:37 PM
Author: John Pollard

Date: 8/12/2009 5:14:23 PM
Author: Rockdiamond
Fancydiamond: there is a question I have.
You mention the diamond looks cloudy in the center. That is generally not something attributable from the cut. Certainly the stats of your stone don''t indicate anything what would cause cloudiness.
I''m wondering if there are other aspects coming into play here.
What are the GIA color and clarity?

In my experience consumers sometimes use ''cloudy'' to describe table reflection in some lighting - as opposed to the trade where we automatically connect the term to clarity or overfluorescence.

<< All I know is that in real life the stone has acceptable though not great sparkles and fair contrast (the center looks cloudy). >>

In this case I interpreted cloudy as table reflection. It would make sense given the combo and especially when seeing TR show as blue in the ASET: The areas circled below show how table reflection impacts the stated parameters in a perfect wireframe simulation (L) and how the actual diamond has a larger, asymmetric area of table reflection caused by its cut particulars (R).

Fancy, if you''re seeing something other than this let me know.

It is possible the center of your stone will have a very different effect from stones you generally see.
And clearly it does not have the symmetry of the perfect sym stone I made here with your proportions.
But the light return data on DiamCalc is very good - 1.00 is the generally considered best.

Regarding fire - there will be plenty of fire in the pendant environment, but it probably will not have the same intensity as you would want in a ring.

The stone will loose a lot of diameter but not that much weight if you recut it.
I would not recut it unless you want to use it in a ring.

The stone is also slightly painted by about 2 degrees. This will have the effect of making it look quite large from edge to edge light return.

 

[stone-cold11]

Date: 8/12/2009 9:12:59 PM
Author: FancyDiamond
Attached photo shows how my two diamonds look like. The one on the right is the 1.12 ct in question.

I am beginning to understand that my diamond is a borderline case, and I hear your recommendation. Just to make sure more before I decide. If the recut results in a weight loss of say 10% and a diameter decrease of 5% (guess the spread and table may suffer even more), is it still worthwhile to get the recut for perfect or near perfect light performance? In other words, will the recut diamond look better from 12 inches away?

Not expert here, just another consumer, but from what I understand about the proportion and it''s effect on performance, I would say no to recut. The stone perform just as well as other near tolk stone from 12 inches and further away, so no reason to cut it smaller.

 

[strmrdr]

This is what I would do...
Have it mounted in a simple 6 prong basket pendant setting, silver is fine, wear it for a few weeks and see if you still want to recut it.

 

[allowingtoo]

How about having it set in a bezel? I have a OEC that is not cut optimally - I was going to have it recut. I had it set in a ring and the heart of it kept looking "dark" after a day or so. I had Brian Gavin look at it in pictures and he said he thought it was cut steep deep or something like that. I had it set into a bezel as a next resort and it looks MUCH better. I''m seeing a lot of bezel necklaces on TV lately too but I''ve worn one for about 8 years - I just upgraded the size

 

[MichelleCarmen]

Date: 8/13/2009 10:51:34 AM
Author: strmrdr
This is what I would do...
Have it mounted in a simple 6 prong basket pendant setting, silver is fine, wear it for a few weeks and see if you still want to recut it.

2nd to this. Wear it around and the best way to see if it performs decently is *as a pendant*, next time your in your car and it''s sunny out, see what kind of colorful rainbows you can make appear on your steering wheel and dash board as the diamond catches the light.

If you become mezmorized and begin swevering all over the road, you''ll know the diamond is worth keeping as is.

 

[Ellen]

Date: 8/13/2009 4:11:16 PM
Author: MC
2nd to this. Wear it around and the best way to see if it performs decently is *as a pendant*, next time your in your car and it''s sunny out, see what kind of colorful rainbows you can make appear on your steering wheel and dash board as the diamond catches the light.

If you become mezmorized and begin swerving all over the road, you''ll know the diamond is worth keeping as is.

 

[canuk-gal]

HI:

IMHO, if it is destined for a pendant and you've already stated it looks great "at a distance" then I say do not sacrifice diameter/weight in a recut. Since most people will be viewing your pendant from a distance greater than 12 inches, it is all good! (if they are closer, however, smack them...

)

cheers--Sharon

 

[Yimmers]

Date: 8/13/2009 8:26:51 PM
Author: canuk-gal
HI:


IMHO, if it is destined for a pendant and you''ve already stated it looks great ''at a distance'' then I say do not sacrifice diameter/weight in a recut. Since most people will be viewing your pendant from a distance greater than 12 inches, it is all good! (if they are closer, however, smack them...

)


cheers--Sharon

lol!

 

[Lorelei]

Date: 8/13/2009 5:02:16 PM
Author: Ellen

Date: 8/13/2009 4:11:16 PM
Author: MC
2nd to this. Wear it around and the best way to see if it performs decently is *as a pendant*, next time your in your car and it''s sunny out, see what kind of colorful rainbows you can make appear on your steering wheel and dash board as the diamond catches the light.

If you become mezmorized and begin swerving all over the road, you''ll know the diamond is worth keeping as is.

Ingenious!