Si2 plot help

[ozzie227]

Hi all - I am new here - and trying to pick out a ring for my future fiancé. I am leaning towards the attached GIA report, but want opinions on the clarity plot. I saw the diamond in person and wasn’t able to identify any noticeable inclusions, but I don’t have a trained eye and want to understand whether there are any serious red flags based on the certificate (understanding the Certificate isn’t necessarily the whole story). Any help provided is appreciated on the clarity specifically, or stone generally! I liked the stone in person, but just want to gather some additional thoughts

 

[DejaWiz]

I'm going to start with a visual aid:




Just some nitpicking of ranges to stick with, based on my personal preferences (in no particular order):
1. Table width: 53-58%
2. Crown height: 15-15.5%
3. Pavilion angle: 40.6-41.0°
4. Crown angle: 34-35°
5. Pavilion depth may be a touch too deep at 44.5%

The LGF of 75% is great and should allow for some nice thick arrows patterning.

The primary area of concern for me would be the 41.8° PA, which is probably going to lead to a ton of light leakage. It may look great as a loose stone since lighting is permitted to enter through the pavilion area while viewing it, but it has a high probability of going dark/dead once set and light is no longer entering the diamond in that manner.

Be sure to ask them to place it in a mock-up setting and allow you to view it that way in a variety of lighting conditions, including direct/sunlight and indirect/diffused.

Here's a more technical explanation:

HCA - defining ideal cut diamonds

To play it safe, I recommend that you look for alternative candidates that have better proportions and angles.

 

[lovedogs]

I'm going to start with a visual aid:




Just some nitpicking, based on my personal preferences (in no particular order):
1. Table width: 53-58%
2. Crown height: 15-15.5%
3. Pavilion angle: 40.6-41.0°
4. Crown angle: 34-35°
5. Pavilion depth may be a touch too steep at 44.5%

The LGF of 75% is great and should allow for some nice thick arrows patterning.

The primary area of concern for me would be the 41.8° PA, which is probably going to lead to a ton of light leakage. It may look great as a loose stone since lighting is permitted to enter through the pavilion area while viewing it, but it has a high probability of going dark/dead once set and light is no longer entering the diamond in that manner.

Be sure to ask them to place it in a mock-up setting and allow you to view it that way in a variety of lighting conditions, including direct/sunlight and indirect/diffused.

Here's a more technical explanation:

HCA - defining ideal cut diamonds

To play it safe, I recommend that you look for alternative candidates that have better proportions and angles.

I agree

 

[evergreen]

Clarity is at least 80% a personal preference - what does your intended think? The crystal on the table could be impossible to see if it's clear or white, or a big black blob that will bother her every time she looks at the ring. ("Impossible to see" is also an individual thing - my eyes are under 40 but I have a hard time seeing even black inclusions in set SI2s in person sometimes.) A 3ct stone with a black table inclusion would still, for me, be less preferable than a 2.5ct stone with something I couldn't see. So, you've told us you can't see it, but how good are you generally at seeing diamond inclusions? Did the salesperson show you any diamonds you found unacceptable from a clarity perspective? And do you know how your future fiance balances clarity concerns vs size?

 

[monipod]

I don't baulk at moderately included stones (I have many) but for an engagement ring and for stones over 2ct, I'd rather up the clarity and downgrade the size. If your priority is size and you and your fiancee genuinely can't see the inclusions, then maybe it's ok. I can't help but think that cloud on the table will be annoying visually over time.

 

[Garry H (Cut Nut)]

I'm going to start with a visual aid:




Just some nitpicking of ranges to stick with, based on my personal preferences (in no particular order):
1. Table width: 53-58%
2. Crown height: 15-15.5%
3. Pavilion angle: 40.6-41.0°
4. Crown angle: 34-35°
5. Pavilion depth may be a touch too deep at 44.5%

The LGF of 75% is great and should allow for some nice thick arrows patterning.

The primary area of concern for me would be the 41.8° PA, which is probably going to lead to a ton of light leakage. It may look great as a loose stone since lighting is permitted to enter through the pavilion area while viewing it, but it has a high probability of going dark/dead once set and light is no longer entering the diamond in that manner.

Be sure to ask them to place it in a mock-up setting and allow you to view it that way in a variety of lighting conditions, including direct/sunlight and indirect/diffused.

Here's a more technical explanation:

HCA - defining ideal cut diamonds

To play it safe, I recommend that you look for alternative candidates that have better proportions and angles.

A message really just to you DW. Crown height and pavilion depth are rather meaningless.
Crown height is simply a function of crown angle and table size (and 53% is a bit on the small side depending on girdle thickness - see Jaspers page here http://www.folds.net/diamond_girdle/index.html )
If both are right then height is a given. Personally I prefer to give people broarder ranges too as maybe not everyone is a Cut Nut.

The same is true for pavilion depth % - light can not care about percentages but it loves angles and behaves and performs for them.

Do you not like this chart?

 

[DejaWiz]

A message really just to you DW. Crown height and pavilion depth are rather meaningless.
Crown height is simply a function of crown angle and table size (and 53% is a bit on the small side depending on girdle thickness - see Jaspers page here http://www.folds.net/diamond_girdle/index.html )
If both are right then height is a given. Personally I prefer to give people broarder ranges too as maybe not everyone is a Cut Nut.

The same is true for pavilion depth % - light can not care about percentages but it loves angles and behaves and performs for them.

Do you not like this chart?

I love that chart!
My advice to others stems from the ranges that a few places (including Whiteflash) define as super ideal, which fits into the green column and mostly into the adjacent light orange columns.

 

[sledge]

@ozzie227, I would be extremely cautious with this purchase. Point blank, the vast majority of SI2 stones are not eye clean. The likelihood of larger stones (especially in the 3+ carat range) being eye clean is even more rare. Do some exist? Maybe. But manage your expectations accordingly, as this would be a unicorn type purchase.

The problem with looking at a lab report only is two fold. The grade setting inclusion on this stone is a crystal, likely what appears as the large one on the table. What the report doesn’t tell us is if it’s black, clear or milky/cloudy looking. Also while the report identifies location they aren’t done “to scale” meaning the report identifies general location but it could be smaller or larger.

Also, while “clouds not shown” in the notes section isn’t too worrisome to me in higher clarity stones, it does concern me in SI2. In a lower clarity stone this could translate to a transparency issue which means the stone may look hazy, cloudy or milky. It would become more obvious in spotlight type lighting.

I am not trying to scare you, but IMO, this is indeed a risky purchase and I hope I have conveyed that properly. You need to carefully vet the stone. If you lack the expertise, it would be worthwhile to pay for an independent appraisal and to express concerns for clarity. Alternatively, if the vendor has a video, that may be useful in helping make a more educated assessment online but may still not be as revealing as in-person. Obviously the jeweler selling the stone will tell you it’s well cut, gorgeous and eye clean but that is to be expected as he/she has bias towards making a sale. Very few jewelers can remove their bias from the equation, so please keep that in mind as well as this is a fairly large purchase (guessing $35-40k).

I would strongly encourage you to read this article about clarity. It will go over many points I could blabber on about. If something isn’t clear, post back and we can deep dive as necessary.

Diamond Clarity: Everything You Need To Know

What is the best diamond clarity? Our extensive guide and interactive diamond clarity chart shows you everything you need to know.

www.pricescope.com

 

[oldminer]

The thread was initially about a clarity plot. The information on a clarity plot can be useful to re-identify a diamond or warn the potential buyer of things which may affect the looks of the diamond. The plot has nothing to do with proportions and percentages. Most consumers don't need much beyond GIA3EX and the predictive HCA and Looks Like scores when it comes to cutting. A relatively smaller number of consumers further perfection of the cut and that is what AGS000 plus the premium cutting add-ons of just a handful of boutique vendors offer. There is a difference, but premium cut diamonds are not the major interest of average consumers.

The worry on the diamond in question is how extensive and translucent the "clouds not show" are. I tend to avoid recommending them sight unseen. You need to look at them closely to determine what effect, if any, such clouds have, With Si and I1 diamonds, you need to look at eye-visibility of inclusions without magnification, too. There is a ton of information within Pricescope on these clarity topics, but responses should not re-direct a topic to another large and even more challenging topic. I hope you'll agree.....

 

[Philmc99]

A message really just to you DW. Crown height and pavilion depth are rather meaningless.
Crown height is simply a function of crown angle and table size (and 53% is a bit on the small side depending on girdle thickness - see Jaspers page here http://www.folds.net/diamond_girdle/index.html )
If both are right then height is a given. Personally I prefer to give people broarder ranges too as maybe not everyone is a Cut Nut.

The same is true for pavilion depth % - light can not care about percentages but it loves angles and behaves and performs for them.

Do you not like this chart?

Regarding this chart, is there a reason why it does not include depth ranges?

 

[sledge]

Regarding this chart, is there a reason why it does not include depth ranges?

It doesn’t include girdle thickness either, but generally speaking you want to stay thin to slightly thick. Very thin creates chip risk. Anything over slightly thick puts a little too much junk in the trunk and likely diminishes light return as the stone is cut for weight and not beauty.

Crown height and pavilion depth will change according to table size, crown angle and pavilion angle. The summation of crown height, girdle thickness and pavilion depth will create total depth.

General guideline for total depth is 60 to about 62.5 depth overall. Large table, shallow crown and shallow pavilion will be on the lower side of that. Smaller table, steeper crown and steeper pavilion will be on the upper side of that. Performance and personality may change based on all those variables as Garry’s chart roughly identifies (balanced, firey, bright, etc).

If you have more specific questions, please start a new thread so we don’t pollute the OP’s thread about clarity.

 

[ozzie227]

Thanks all for the helpful responses! It is a sizeable purchase and a big decision, so I'm glad i gathered additional thoughts. On the cut comments, I was satisfied with the triple excellent rating on the certificate, but it is good to know there are also other considerations. Regarding the clarity - I will try to get additional photos / videos, because my eye is not trained. I think my girlfriend would prefer a 3 carat / size over high clarity - but I may have to ask her directly. I chose to prioritize in the following order: cut, size, color, then clarity - and SI diamonds are what is in my price range for a triple excellent, ~3 carat, near colorless diamond. I am obviously concerned about the clarity hence my original post - but having trouble with the tradeoffs and keeping it in budget. you all gave me a lot to think about and i may have to get answers directly from my gf - thanks!

 

[DejaWiz]

@Garry H (Cut Nut) and @oldminer Because this thread is about clarity instead of all the measurements and proportions, I can take a hint at whom you're directly and indirectly calling out and you're right: I often get lost in the minutia of a vert tight set of ranges which can (and will) lead to skipping over perfectly acceptable and beautifully performing diamonds. Duly noted and I will work on that when providing feedback to fellow forum members seeking advice. I jumped right into the deep end of the diamond pool and didn't even bother speaking towards the clarity.
My approach was that the pavilion and crown angles are seemingly out of whack, so have the seller place it in a mock-up setting to be sure how it will perform in a variety of lighting conditions.
What I forgot to add (since I got lost in the nuances of proportions and angles) was that viewing it that way (in a setting) would be the best way to gauge whether those inclusions become quite evident and mess with the light return and overall performance.

Since @sledge, @evergreen , and @oldminer have already commented adequately about the clarity, so I won't go into elaborate thought regarding the plot map. Here is my simplified version:

@ozzie227 the inclusions under the table could be a very huge concern, so it is imperative to see how obvious they stand out while this diamond is set in a ring instead of being viewed as a loose diamond.

 

[Garry H (Cut Nut)]

Regarding this chart, is there a reason why it does not include depth ranges?

Depths mean zippo zilch and nothing.
There are beautiful diamonds (with smaller spreads because the girdles are thicker) up to and above 63% (should be GIA VG) that can suit some peoples need for price and a carat weight to keep the out-laws happy.

 

[Garry H (Cut Nut)]

Thanks all for the helpful responses! It is a sizeable purchase and a big decision, so I'm glad i gathered additional thoughts. On the cut comments, I was satisfied with the triple excellent rating on the certificate, but it is good to know there are also other considerations. Regarding the clarity - I will try to get additional photos / videos, because my eye is not trained. I think my girlfriend would prefer a 3 carat / size over high clarity - but I may have to ask her directly. I chose to prioritize in the following order: cut, size, color, then clarity - and SI diamonds are what is in my price range for a triple excellent, ~3 carat, near colorless diamond. I am obviously concerned about the clarity hence my original post - but having trouble with the tradeoffs and keeping it in budget. you all gave me a lot to think about and i may have to get answers directly from my gf - thanks!

Then find a diamond that has eye visible inclusions because in that size there are no nice eye clean safe SI2's

 

[Lookinagain]

I think my girlfriend would prefer a 3 carat / size over high clarity - but I may have to ask her directly. . . you all gave me a lot to think about and i may have to get answers directly from my gf - thanks!

I think this is wise. Often times people say "I want a 3 ct diamond". They don't say anything else and assume any diamond will look the way they expect it to. A diamond with visible inclusions may not. Or you may find that your gf isn't color sensitive and would be happy with an H, I or even J stone. This would open you up to other options and still keep you in budget. Also, she may not have any idea of the cost of the 3 ct. diamond she is envisioning. We don't know how educated she is about diamonds and it doesn't seem as if you've asked her what she likes. Take her to a few jewelry stores and have her try on some rings of different sizes and color and clarity and get some idea of what is important to her. If you have already done this, I apologize for giving you advice you don't need, but from what I quoted above from your post I made the assumption that you have not.

 

[evergreen]

I, too, prioritize size over clarity
For example -- all other things being equal, even though this diamond has what looks like a ton of internal graining and probably some clouds that impact light return, and probably has a really busy clarity plot, I would prefer it in a ring compared to this diamond -- the carbon spot under the table would be too obvious for a ring. (Earrings? No problem, haha!)

So, we can't tell enough from the clarity plot to be sure. Magnified photos/videos like you see on James Allen tell a different story than the cert, too: they're so highly magnified and optimized that it ALSO doesn't reflect realistic viewing. I have this diamond https://www.jamesallen.com/loose-di...rat-g-color-si2-clarity-ideal-cut-sku-9836548 set in a ring and I can barely find the inclusions.

 

[Garry H (Cut Nut)]

I, too, prioritize size over clarity
For example -- all other things being equal, even though this diamond has what looks like a ton of internal graining and probably some clouds that impact light return, and probably has a really busy clarity plot, I would prefer it in a ring compared to this diamond -- the carbon spot under the table would be too obvious for a ring. (Earrings? No problem, haha!)

So, we can't tell enough from the clarity plot to be sure. Magnified photos/videos like you see on James Allen tell a different story than the cert, too: they're so highly magnified and optimized that it ALSO doesn't reflect realistic viewing. I have this diamond https://www.jamesallen.com/loose-di...rat-g-color-si2-clarity-ideal-cut-sku-9836548 set in a ring and I can barely find the inclusions.

That is what I am talking about - your stone - some serious but small inclusions hardly if ever affecting the light performance.
For the OP - 2 things to try - a fancy shape - they are 25-35% cheaper.
OR
A VG cut quality with a thick girdle but great proportions.

 

[sledge]

@ozzie227 I would be glad to recommend some alternate stones for you. What kind of a budget do you have to work with?

I agree you should ask your girlfriend to prioritize. She’s going to wear it, so it makes sense whatever you buy makes her happy.

Prior to COVID I bought my wife a full size luxury SUV. However, she had requirements, lol. Certain trim package, a whooping two color choices and if used it couldn’t be more than 1 year old and have stupid low miles. She was picky and I was proud of her for defining her desires. She does so much for me and our family and I wanted her to get exactly what she wanted. She rarely does that so the extra time & effort was worthwhile to see her smile everyday when she drives.

We can help pick you out a diamond with no problems. Even if clarity did work, I would prefer more favorable proportions. Even using Garry’s “liberal” chart, you may have noticed a 41.8 pavilion never made the list.

Depending how far down the rabbit hole you wish to go we can talk more about cut. I will say that not all 3X stones are all that. You have to look at the details.

Let us best know how we can help you.