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Kashmira

Kashmira

Shiny_Rock
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Aug 16, 2009
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I''m trying to learn more about diamonds and have a few questions regarding the cut:

* Can a really really good cut compensate for a "lower" colour grade (for example K or L) and make a K or L coloured diamond look like a G or H coloured diamond that has a "normal" cut?

* Is H&A the "best" cut?

* If looking at for example the webpage of BlueNile they have Signature Ideal cut, Ideal cut, Very good cut, Good cut, Fair cut and Poor cut. Is "very good" a "good" cut? Is it possible to see a difference with the unaided eye between for example a "Ideal cut" and "very good" cut?

* Is it correct that GIA uses Excellent, Very Good, Good, Fair and Poor to describe the quality of the cut? And if yes, does Signature Ideal cut (BlueNile) correspond to "Excellent"`and "Ideal cut" with "very good"?



 
Date: 12/23/2009 4:25:35 AM
Author:Kashmira





I'm trying to learn more about diamonds and have a few questions regarding the cut:

* Can a really really good cut compensate for a 'lower' colour grade (for example K or L) and make a K or L coloured diamond look like a G or H coloured diamond that has a 'normal' cut? Cut can make a big difference in the beauty of the stone and can help a lower colour face up whiter but not to that extent I don't think. There are other factors that can influence apparent colour too such as size and shape of the diamond, fluorescence etc.

* Is H&A the 'best' cut? This depends, to some yes it is the best cut, the branded h&a diamonds we see here are usually of the highest cut quality both for optical precision and optical performance. But if you aren't concerned with picture perfect h&a a ' near' h&a or just a well cut diamond could fit the bill perfectly.

* If looking at for example the webpage of BlueNile they have Signature Ideal cut, Ideal cut, Very good cut, Good cut, Fair cut and Poor cut. Is 'very good' a 'good' cut? Is it possible to see a difference with the unaided eye between for example a 'Ideal cut' and 'very good' cut? Possibly but this is a hard one to answer as we don't know what criteria BN use to assign cut grade descriptions to their diamonds for the most part. Always evaluate each on its own desirable physical properties if shopping with BN as they don't provide images.

* Is it correct that GIA uses Excellent, Very Good, Good, Fair and Poor to describe the quality of the cut? And if yes, does Signature Ideal cut (BlueNile) correspond to 'Excellent'`and 'Ideal cut' with 'very good'? Yes. Again though don't rely on cut labels as these can be deceptive, however the BN Signature Ideals are generally very well cut, with the other cut grades other factors can come into play so these are no guarantee of any level of cut quality.

Really you would get more specific answers if you had actual diamonds to compare, do you have any you are thinking of?






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Date: 12/23/2009 4:25:35 AM
Author:Kashmira
I''m trying to learn more about diamonds and have a few questions regarding the cut:

* Can a really really good cut compensate for a ''lower'' colour grade (for example K or L) and make a K or L coloured diamond look like a G or H coloured diamond that has a ''normal'' cut?
Click to expand...
I''m not professional. My opinion is: an excellent cut K-L can look like a not so well cut I-J.

* Is H&A the ''best'' cut?
Click to expand...
If the H&A is cut to tight proportions (Brian Gavin Diamonds, Whiteflash, Crafted by Infinity, ...), a H&A will be the best balanced round diamond for almost every taste.
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* If looking at for example the webpage of BlueNile they have Signature Ideal cut, Ideal cut, Very good cut, Good cut, Fair cut and Poor cut. Is ''very good'' a ''good'' cut?
Click to expand...
I would say yes.

Is it possible to see a difference with the unaided eye between for example a ''Ideal cut'' and ''very good'' cut?
Click to expand...
Not always but often.

* Is it correct that GIA uses Excellent, Very Good, Good, Fair and Poor to describe the quality of the cut?
Click to expand...
Yes!

And if yes, does Signature Ideal cut (BlueNile) correspond to ''Excellent''`and ''Ideal cut'' with ''very good''?
Click to expand...
False.
BlueNile Signature = GIA EX cut
BlueNile Ideal cut = GIA EX cut too.
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Date: 12/23/2009 4:25:35 AM
Author:Kashmira
I'm trying to learn more about diamonds and have a few questions regarding the cut:

* Can a really really good cut compensate for a 'lower' colour grade (for example K or L) and make a K or L coloured diamond look like a G or H coloured diamond that has a 'normal' cut?
Click to expand...
All these are assuming you are talking about a round, as fancys will not have H&A patterning.
Depends on the actual proportion, not way to predict from just the assigned cut grade.
* Is H&A the 'best' cut?
Click to expand...
Not necessary, H&A is an example of excellent optical symm, not all stones of excellent optical symm will qualify for traditional definition of H&A, it also does not automatically equate to optical performance. A stone can have excellent optical symm, with a traditional H&A patterning and still be performing less than ideal because of bad proportions. For optical symm, we will need to see a Hearts and an Arrows image taken with a H&A scope. For optical performance, will need an Idealscope image. BN will not be able to supply these images.
* If looking at for example the webpage of BlueNile they have Signature Ideal cut, Ideal cut, Very good cut, Good cut, Fair cut and Poor cut. Is 'very good' a 'good' cut? Is it possible to see a difference with the unaided eye between for example a 'Ideal cut' and 'very good' cut?
Click to expand...
Again, depends on the actual proportion of the stone rather than the assigned cut grade.
* Is it correct that GIA uses Excellent, Very Good, Good, Fair and Poor to describe the quality of the cut? And if yes, does Signature Ideal cut (BlueNile) correspond to 'Excellent'`and 'Ideal cut' with 'very good'?
Click to expand...
Yes to GIA cut grade. BN SI stones alway have an GIA Ex or AGS0 cut grade, their in-house stones, those they actually owns. BN's ideal cut grade are given generally to stones with GIA Ex or AGS0 cut graded stones.
 
An exceptionally well cut stone makes it brighter, which tends to have a "wash out" effect on the colour tint. So, yes, an exceptional cut will often appear one or two colour grades higher when there is strong ambient light for it to reflect and "bleach" any colour tint. In medium or low light, or when the stone is illuminated from certain angles, the body colour will become more noticeable.

H&A is often present in well cut stone, but H&A in itself only refers to perfect symmetry. More important than symmetry is the details of the proportions. If the angles are bad combinations, the perfect symmetry will actually make the stone look worse.

Bluenile Signatures seem to be the better-proportioned of the GIA Excellent stones and seem to rival the AGS0 or AGS1 grades. Having looked at a some "virtual" BN stone certs in the past, I've yet to see a true "steep/deep" among their signature stones. I regard BN signature as the "super ideal" grades at the heart of the GIA Excellent cut (where GIA should have allocated an "ideal" grade, above their "excellent" grade).
BN signatures also seem to generally include no stones with strong fluor (
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) and no stones with SI2 (
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). It would seem to be that way to ensure that the stones will be sparkly, pleasing, eye-clean-ish and uncontroversial to almost everyone. Fluor and SI2 will not please everyone - and fluor has a particularly bad reputation (unfairly, IMO).
 
Date: 12/23/2009 4:25:35 AM
Author:Kashmira

In my opinion:

* Can a really really good cut compensate for a ''lower'' colour grade (for example K or L) and make a K or L coloured diamond look like a G or H coloured diamond that has a ''normal'' cut?

No. It will make those colors look brighter and whiter face up in the type of lighting you have outside on a cloudy day. It will not make them look like a colorless diamonds, and inside and in low lighting you will not get much oomph from the cut. I have owned a K so this is from personap experience. Warm diamonds are gorgeous but you muct accept that they are warmer and love them for it.

* Is H&A the ''best'' cut?

Sort of. You can also get a super ideal cut by the numbers that is not technically an H&A and you can save money that way.

* If looking at for example the webpage of BlueNile they have Signature Ideal cut, Ideal cut, Very good cut, Good cut, Fair cut and Poor cut. Is ''very good'' a ''good'' cut? Is it possible to see a difference with the unaided eye between for example a ''Ideal cut'' and ''very good'' cut?

All websites vary in how they label things. You need to go by what the cert says to know what you are really getting.

* Is it correct that GIA uses Excellent, Very Good, Good, Fair and Poor to describe the quality of the cut? And if yes, does Signature Ideal cut (BlueNile) correspond to ''Excellent''`and ''Ideal cut'' with ''very good''?

No, I don''t think so. Again, you need to check the certs to be sure.




Click to expand...
 
Date: 12/23/2009 2:23:25 PM
Author: dreamer_dachsie
Date: 12/23/2009 4:25:35 AM
Author:Kashmira
* Is it correct that GIA uses Excellent, Very Good, Good, Fair and Poor to describe the quality of the cut? And if yes, does Signature Ideal cut (BlueNile) correspond to ''Excellent''`and ''Ideal cut'' with ''very good''?

No, I don''t think so. Again, you need to check the certs to be sure.
Click to expand...
Click to expand...
BlueNile Signature with GIA document = GIA EX cut
BlueNile Ideal cut with GIA document = GIA EX cut too.
If the cert is AGS they sometime do mistakes.
 
Date: 12/23/2009 2:32:00 PM
Author: QueenMum

Date: 12/23/2009 2:14:13 PM
Author: FB.
Having looked at a some ''virtual'' BN stone certs in the past, I''ve yet to see a true ''steep/deep'' among their signature stones.
Click to expand...
Here you are:
http://be.bluenile.co.uk/round-diamond-1-carat-or-less-signature-ideal-cut-d-colour-vs1-clarity_LD01603317
http://be.bluenile.co.uk/round-diamond-1-carat-signature-ideal-cut-i-colour-vs2-clarity_LD01600998
If you need more, just ask me.
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I stand corrected.
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Thanks everyone for your replies! The more I try to learn about diamond the more I realize that I know almost nothing. I am looking into buying a pair of diamond studs and I now know what to look for in terms of colour and clarity but it''s harder with the cut...
 
Everyone has already said pretty much everything I would have much more eloquently
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.


I do want to comment on one thing, though. You ask if H&A is the "best" cut, and my reply is more a general statement: the only way for YOU to know is to go out and look at some rounds with different personalities and find the type that makes your heart sing.


H&A, like others have said, guarantees perfect optical symmetry by definition. The PS vendors who sell branded H&A stones aren't just selling stones that fit that base definition of perfect optical symmetry, however, they're selling stones that fit a certain mold (certain combinations of numbers/angles that are general crowd-pleasers) that also have perfect optical symmetry. You can have a technically H&A stone that looks bizarre because it's much too shallow or too deep, and no PS vendor will sell it as part of their H&A line because it has numbers that fall outside the rest of the brand requirements (this is, of course, true only to the extent that you can change the numbers and still get those hearts and arrows patterns)..


That probably didn't make any sense. The point I'm trying to make is that when I was looking for my forever stone, having had a shallower almost-H&A (I had a WF ES) my preference was for something that strongly favours fire over white light return. FI and I were committed to WF, and it was important to both of us to have an RB, so cushions and OECs and other traditionally "fiery" stones weren't options. I wanted a stone with perfect hearts and arrows patterns, and I was happy to pay the premium, but I also wanted a 36+ crown and appropriate pavilion, and these angles fall outside the tight set of numbers that the ACA brand requires (and I didn't want to wait for a stone to be specifically cut) so I found an excellent non-H&A stone with a picture perfect IS and I'm thrilled with it. For ME, this particular non-H&A is the "best" cut.







Stepping off the soapbox now
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yssie, you have a FIC but you didn''t post pictures?!?
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Stunning! I love it!
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yssie! Your ring is beyond gorgeous - I LOVE LOVE LOVE it!

What''s "a FIC"? Also does anyone know what European PC vendors there are?
 
FIC is a Fiery Ideal Cut. This type of stone usually has a slightly shallower pavillion (40.4-40.6) and higher crown (36 degrees) than a typical Tolkowsky Ideal Cut. They can show more fire in certain lighting than other diamonds, hence the name. They are similar to a lot of antique cuts in this regard, but with modern facet patterns. The only downside is that many are a little deeper and face up smaller than a traditional ideal cut of the same weight.

The only European vendors I know of with PS ties are Crafted by Infinity dealers--Dr. Indira Marchant in England posts on PS occasionally.
 
Without quesiton the way a stone is cut affects how much color we see.
However a "well cut" ( by PS definition) stone will not necessarily look whiter in real life because of it's cut.
Sometimes aspects of a cut that would cause people here to say it's less well cut ( such as a slightly larger table) will make it show less color. Sometimes not. It so much varies stone to stone.

I love J-K-L color stones. In my experience, how yellow they look is really a crapshoot.
Sometimes a J color will look yellowish face up, sometimes not.
But it's not necessarily associated with a specific cut such as "Heart and Arrows".

If you are buying from a dealer that can personally evaluate the stone, you should get an answer about a particular stone.
If the seller does not have the stone, they can't answer accurately.
They can however use the logic that says "Ideal" shows less color than "non ideal" and try to steer you towards the more expensive "Ideal" or Premium" cut
 
Date: 12/23/2009 6:23:17 PM
Author: Rockdiamond
Without quesiton the way a stone is cut affects how much color we see.
However a ''well cut'' ( by PS definition) stone will not necessarily look whiter in real life because of it''s cut.
Sometimes aspects of a cut that would cause people here to say it''s less well cut ( such as a slightly larger table) will make it show less color.





I love J-K-L color stones. In my experience, how yellow they look is really a crapshoot.
Sometimes a J color will look yellowish face up, sometimes not.
But it''s not necessarily associated with a specific cut such as ''Heart and Arrows''.

If you are buying from a dealer that can personally evaluate the stone, you should get an answer about a particular stone.
If the seller does not have the stone, they can''t answer accurately.
They can however use the logic that says ''Ideal'' shows less color than ''non ideal'' and try to steer you towards the more expensive ''Ideal'' or Premium'' cut
Click to expand...
Do you have any proof for that statementI can''t find any and it doesn''t even appear logical or scientific.

The colors perceived of objects are the results of interactions between the various frequencies of visible light waves and the atoms of the materials which objects are made of. Many objects contains atoms capable of either selectively absorbing, reflecting or transmitting one or more frequencies of light. The frequencies of light which become transmitted or reflected to our eyes will contribute to the color which we perceive.

In very simplified terms the diamonds color seen is the color of light NOT absorbed or the complimentary color to the strongest light being absorbed.
Near colorless diamonds appear yellow because they absorb blue/violet light. The more efficient this absorption of blue/violet light the more yellow we see in the diamond and the more saturated the color is.

However diamonds reflect/transmit a mix of Red/Green (to make Yellow) AND White Light. (assuming the source is white light)

The better the light return of the diamond the more pure white light is transmitted along with the yellow and the whiter the color will appear.

Better Light Return ~ Less Color Perceived
and therefore
Better Cut > Better Light Return = Less Color Perceived

We prefer on PS the better light return (ie no leakage) so these stones would show LESS color not more than your 60/60 or other cuts which have leakage.
This is also why round brilliant cut diamonds which have more efficient light return than most fancy cuts appear faceup whiter.

Are you confused yourself or just trying to confuse others once again?
 
*sigh*
ok, there is a bit of truth that all else equal an ideal cut diamond with a 60% table will show less color with the same crown/pavilion angles and lgf%.
Change any angle and that might or might not hold true.

2 reasons it would be so:
Shallower crown == less material
larger table favors white light return which masks color.

When you look at what is on the market since no one is cutting well cut 60% tabled diamonds on a consistent basis anymore the statement that tolk diamonds on the market hide color better is true most of the time.

Just saying a larger table hides color better is like saying a blue car is faster than a red car.
*sigh*
 
Date: 12/23/2009 7:59:29 PM
Author: Karl_K
*sigh*
ok, there is a bit of truth that all else equal an ideal cut diamond with a 60% table will show less color with the same crown/pavilion angles and lgf%.
Change any angle and that might or might not hold true.

2 reasons it would be so:
Shallower crown == less material
larger table favors white light return which masks color.

When you look at what is on the market since no one is cutting well cut 60% tabled diamonds on a consistent basis anymore the statement that tolk diamonds on the market hide color better is true most of the time.

Just saying a larger table hides color better is like saying a blue car is faster than a red car.
*sigh*
Click to expand...
Sure theoretically, but the lack of depth would counter that.
Its not just 60 its 60/60depth and a shallower crown.

Can you do the comparison quantitatively in absolute light return ignoring color for a moment?
 
Date: 12/23/2009 7:59:29 PM
Author: Karl_K
*sigh*

ok, there is a bit of truth that all else equal an ideal cut diamond with a 60% table will show less color with the same crown/pavilion angles and lgf%.

Change any angle and that might or might not hold true.


2 reasons it would be so:

Shallower crown == less material

larger table favors white light return which masks color.


When you look at what is on the market since no one is cutting well cut 60% tabled diamonds on a consistent basis anymore the statement that tolk diamonds on the market hide color better is true most of the time.


Just saying a larger table hides color better is like saying a blue car is faster than a red car.

*sigh*
Click to expand...
sigh....

Karl, it seems we are in complete agreement.
We agree that a diamond with a slightly larger table can ( if other aspects are there) show less body color than another diamond of the same color with a smaller table.
Of course there can be examples that won''t act this way, if other details of the cut are not in line.
However, there could also be larger tabled stones downgraded for issues regarding symmetry, or polish not visible to the eye, that would also behave as the first case.

We agree smaller tabled diamonds are more common nowadays.

We agree that just saying a certain cut is the best for color is like saying a blue car is faster than a red one.

I believe Kashmira''s excellent thread highlights an aspect of diamond advertising that is confusing to consumers.
Companies such as Blue Nile arbitrarily assign cut grades to stones leading to confusion.
Karl, do you agree that the only cut grades that have true relevance to consumers are those issued by either GIA, or AGSL, and no one else.
 
First of all- thank you everyone for taking your time to reply to my questions! As a newbie when it comes to diamonds it is for sure not easy to know what to look for and the more I try to learn the more difficult I think it is but I am now working with a jeweller who hopefully can help me to get what I want.


Date: 12/23/2009 5:38:34 PM
Author: jet2ks
FIC is a Fiery Ideal Cut. This type of stone usually has a slightly shallower pavillion (40.4-40.6) and higher crown (36 degrees) than a typical Tolkowsky Ideal Cut. They can show more fire in certain lighting than other diamonds, hence the name. They are similar to a lot of antique cuts in this regard, but with modern facet patterns. The only downside is that many are a little deeper and face up smaller than a traditional ideal cut of the same weight.

The only European vendors I know of with PS ties are Crafted by Infinity dealers--Dr. Indira Marchant in England posts on PS occasionally.
Click to expand...
Tolkowsky Ideal Cut- is that the "perfect" cut? I have heard of "Lazare diamonds" as perfectly cut diamonds...
 
re. "very good" cut: It may have "sloppy" arrows or no arrows, or some "off" symmetry, but still be a very good performer. But won't have H&A symmetry, or may be a shallow or deep diamond, or may be cut more for brilliance than fire, or have a large table, or whatever. I have several older cut diamonds that are kind of "random" in their symmetry, but are still pretty to look at. I also have a modern superideal H&A from Good Old Gold. I like them all. But the modern cuts have their dimensions and angles and symmetry tweaked and their polish superbly done to provide a diamond that performs well, and has a balance of fire and brilliance, regardless of the lighting conditions. The older cuts may not be quite as good in all lights.

For color, a modern H&A G will be very white. For J/K/L, there's no way that these will look like G or H ,regardless of cut. Even if they are "white" face up, there is still body tint, and that tint will be a bit of a chameleon in different lights, so sometimes you'll see that tint, a lot, lol.

These are some threads that deal with I/J/K colors. I once tried to get some compiled for L through O, but until GOG recently started the new OEC and cushion cuts in lower colors, there was nothing much posted for L and below.

I:
https://www.pricescope.com/community/threads/i-color-stones-in-platinum.9689/
https://www.pricescope.com/community/threads/is-there-thread-for-i-color-stones.39886/

J:
https://www.pricescope.com/community/threads/j-color-stones-in-platinum.24731/
https://www.pricescope.com/community/threads/2-04ct-j-si2-in-platinum-tiffany-solitaire-from-niceice.12734/

K:
https://www.pricescope.com/community/threads/k-color-stones-in-platinum-wg.43782/
https://www.pricescope.com/community/threads/platnium.11247/
https://www.pricescope.com/community/threads/james-meyer-bezel-reset-has-arrived.97999/

Over in show My The Ring, we started compiling a "helpful threads" list. Check that out.
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Date: 12/26/2009 3:09:00 AM
Author: Kashmira
First of all- thank you everyone for taking your time to reply to my questions! As a newbie when it comes to diamonds it is for sure not easy to know what to look for and the more I try to learn the more difficult I think it is but I am now working with a jeweller who hopefully can help me to get what I want.





Tolkowsky Ideal Cut- is that the ''perfect'' cut? I have heard of ''Lazare diamonds'' as perfectly cut diamonds...
Click to expand...

Great post kashmira- you bring up a lot of good points!
When LK started with their "Ideal Cut", they attempted to prove their cut was superior to all others.
The problem is, we''re dealing with something that has to do with perception, and beauty.
Is JS Bach the best musician of all time?
Of course we''ll never have a consensus on an answer.

The same sort of quandary will exist whenever we are discussing which diamond cut is "best".
There is a range of parameters that are accepted as "best"- and that range is fairly wide to those people who can appreciate the subtle differences.
 
Date: 12/26/2009 3:09:00 AM
Author: Kashmira
First of all- thank you everyone for taking your time to reply to my questions! As a newbie when it comes to diamonds it is for sure not easy to know what to look for and the more I try to learn the more difficult I think it is but I am now working with a jeweller who hopefully can help me to get what I want.



Date: 12/23/2009 5:38:34 PM
Author: jet2ks
FIC is a Fiery Ideal Cut. This type of stone usually has a slightly shallower pavillion (40.4-40.6) and higher crown (36 degrees) than a typical Tolkowsky Ideal Cut. They can show more fire in certain lighting than other diamonds, hence the name. They are similar to a lot of antique cuts in this regard, but with modern facet patterns. The only downside is that many are a little deeper and face up smaller than a traditional ideal cut of the same weight.

The only European vendors I know of with PS ties are Crafted by Infinity dealers--Dr. Indira Marchant in England posts on PS occasionally.
Click to expand...
Tolkowsky Ideal Cut- is that the ''perfect'' cut? I have heard of ''Lazare diamonds'' as perfectly cut diamonds...
Click to expand...
The Holloway Cut Advisor breaks ideal cut stones into three categories. Tolkowsky Ideal Cut, Fiery Ideal Cut and Brilliant Ideal Cut. The FIC is explained, a BIC favors white light return (brilliance) and shows a little less fire. These diamonds tend to be a bit shallower and have larger tables than a Tolkowsky. They also tend to have a larger spread (face up size for their weight). No one type is better than another, it comes down to personal preference. The Tolkowsky Ideal range tends to be the most popular as it has a good balance of brilliance and fire in the widest variety of lighting conditions. BIC''s and FIC''s have their fans, as well. Truth is that unless you compare them side by side, or look at a LOT of diamonds, the differences are pretty subtle.

Best of luck with your search.
 
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