Ideal cut parameters for Crown and Pavilion angles and Crown Height on an Oval Diamond

[mdl0216]

Having read up on quite a bit of oval diamonds parameters, my search has brought me to the following parameters-
Carat- 1.05- 1.3 (ideally on the larger side)
Color - G or better
Clarity - VS2 or better (possibly SI1 but sometimes I am able to see them with the naked eye when I have looked in person)
Fluorescence - none to faint and possibly medium with a G color stone.
Symmetry - Excellent
Polish - Excellent
Table - 55-60
Depth 60-64

What is recommended for crown and pavilion angles be to to look for in an oval diamond?
Is it just not a consideration with oval diamonds, as I have not found any information any where on the topic.
I know I have seen some material suggestion crown height to be 12-15%.

My budget is 5-7k for a oval, ideally would a better diamond over carat size. Any help and suggestions would be greatly appreciated!

Thanks Michael

 

[Rockdiamond]

Hi Michael,
Welcome to Pricescope!
A few things stand out immediately to me
First- I would not limit polish/symmetry to EX.
The reason is that the difference between EX,VG and G are not perceptible to the eye 99% of the time.
Meanwhile, other aspects that aren't really listed on a GIA report are crucial.
There's been talk lately of "Ideal Cut Oval" and from my perspective, it's all bluff. AGSL is declaring stones "Ideal" but there's no broad agreement whatsoever on that. IMO, AGSL is hurting their own brand by doing this- but that's another story.
There's truly well-cut stones- and they are indeed in the minority of what's out there. But there's no agreed upon "Ideal"

 

[Karl_K]

Hi Michael,

There is no one set or range of angles that are best for a oval.
There are different faceting patterns that are used to cut ovals and each has its own set of proportions that work depending on different factors.
When you change the l/w ratio the needed angles change even with the same facet pattern for example.

What David is talking about is AGS has taken a small subset of the possible faceting patterns and looks possible in well cut beautiful ovals and called it Ideal.
That is why it is near universally ignore in the global market.
The exception being a company familar to many PSers that is being built on AGS ideal as its prime marketing point.

 

[lalala]

There's been talk lately of "Ideal Cut Oval" and from my perspective, it's all bluff.

That is why it is near universally ignore in the global market.

Interesting! Good to know...

There is no one set or range of angles that are best for a oval.

Is this chart accurate or no?

https://www.pricescope.com/wiki/diamonds/oval-cut-diamond

 

[mdl0216]

As far as truly well-cut stones for ovals, is it mainly based on when you look at them and/or certain parameters to follow. Thanks! Any suggestions that would fit in my parameters would be greatly appreciated.

with regards to polish and symmetry....my main concern with symmetry is in regards to possible bulge effect to the diamond. Put agree if it is not discernible from the naked eye, it would not bother me.

 

[Rockdiamond]

Interesting! Good to know...



Is this chart accurate or no?

https://www.pricescope.com/wiki/diamonds/oval-cut-diamond

From my perspective, the chart is not useful. I do respect the author and his ideas- but I have found that restricting by these parameters eliminates some of the prime candidates.
If we're talking about a round diamond, sure, it's far easier to predict how certain parameters affect appearance.
But in pretty much any fancy shape, many other variables are introduced.

with regards to polish and symmetry....my main concern with symmetry is in regards to possible bulge effect to the diamond. Put agree if it is not discernible from the naked eye, it would not bother me.

Michael, this is such a common misconception!
GIA's symmetry grade is not about the overall shape of the diamond, rather it deals with the relationship of facets and how they correspond to other facets.

PS- in re-reading my initial post, my wording was too harsh. Apologies.

 

[mdl0216]

No problem, just by my nature I'm a researcher before I buy (I have been looking for months). I just didn't know how far down the rabbit hole you could go in regards to diamonds. So figure I would come here for some advice. Any examples of possible well-cut stones online that you would recommend within the parameters I gave above? Thanks for your time today!

 

[tyty333]

I'll post a few in your specs that are nice so you know what to look for...
https://www.jamesallen.com/loose-diamonds/oval-cut/1.01-carat-e-color-vvs1-clarity-sku-3731176
https://www.jamesallen.com/loose-diamonds/oval-cut/1.01-carat-e-color-vvs2-clarity-sku-2310658
https://www.jamesallen.com/loose-diamonds/oval-cut/1.03-carat-f-color-vvs2-clarity-sku-3181772
https://www.jamesallen.com/loose-diamonds/oval-cut/1.02-carat-e-color-vs1-clarity-sku-3825187
https://www.jamesallen.com/loose-diamonds/oval-cut/1.01-carat-d-color-vvs2-clarity-sku-3656639
https://www.jamesallen.com/loose-diamonds/oval-cut/1.01-carat-e-color-vvs2-clarity-sku-3471068

Its more important to look at Length x width than carat weight.

Edit...I do not look at numbers because they dont really tell me whether a stone is going to perform
well or not. I look at the stones's faceting pattern and make sure that facets are "lighting up" as the
stone turns. Also look for no dark bow-tie, no or minimal shoulders.

 

[mdl0216]

obviously I forgot to include my search parameters have included 1.35-1.55 for the L/W ratio

 

[mdl0216]

preferably would like to be around the 1.1 if I'm going to go to go oval since I believe I can get a great 1 carat for the price point.

 

[tyty333]

What is your time line? August Vintage Inc. is coming out with a well cut branded oval.
They are not out though. You can check out the video here...
https://www.augustvintageinc.net/new-signature-oval-by-august-vintag

 

[tyty333]

preferably would like to be around the 1.1 if I'm going to go to go oval since I believe I can get a great 1 carat for the price point.

Ovals face up larger than rounds by carat weight (usually). But like I said 1.1 ctw doesnt really mean that much for an oval because you could find a 1 carat
oval that faces up bigger than a 1.1 ctw.

Which do you think your GF would like better? Rounds have better light return. Ovals have a lovely, romantic shape (IMO) and usually face up bigger than a round.

We use this tool to show how stones may face up on a finger...I let it default to 1 carat for a round and an oval but like I said, size on ovals
vary. (this is a size 6 finger)

 

[mdl0216]

Honestly she would like either, I have heard her mention both. Agreed on the oval shape plus its something different than a round. Originally I was shooting for around 1.2 oval, but have a hard time finding everything in one package at my price point.

Just for instance this hits every point aside from medium blue Fluorescence and L/W 1.34
https://www.yadavjewelry.com/diamond/oval-diamond-1.28-carat-g-vs2-yd1592503

Or this being a SI1 grade
https://www.adiamor.com/Diamonds/1....3359?q=rc&utm_source=rarecarat&utm_medium=cpc


I appreciate the suggestions tyty333 from James Allen but if you could find a larger carat 1.2 or point me to show how a smaller carat would just as well based on it faces up. Thanks!

 

[Karl_K]

Interesting! Good to know...



Is this chart accurate or no?

https://www.pricescope.com/wiki/diamonds/oval-cut-diamond

I wish it was, but as much as I respect the person who made it the variables are to great to break down on a simple chart.
A diamond that scores high on that chart may be a good one or it may not.
A diamond that scores low on the chart may be a good one or it may not.
The limited parameters can not define if an oval is well cut or not.

 

[lalala]

I wish it was, but as much as I respect the person who made it the variables are to great to break down on a simple chart.
A diamond that scores high on that chart may be a good one or it may not.
A diamond that scores low on the chart may be a good one or it may not.
The limited parameters can not define if an oval is well cut or not.

Makes MRB's seem so easy... amazing how they have been "perfected" enough to compare to charts.

Is there just not enough interest in other cuts to spend this amount of time perfecting them?

If one were to dedicate hours, months (more than likely years), to perfect a cut, is the return worth it? Or are the standard cuts so ingrained (marketed) to consumers that a new cut or specialized cut is not worth the time because it will be overlooked?

Have serious marketing efforts ever been put into place for specialized cuts?

Sorry, OP not trying to thread-jack. A lot has been on my mind lately...

 

[Karl_K]

Hi lalala,
To answer that properly would take a book.
I also have a bit of conflict of interest as I have a specialty cut Asscher I designed and my partner/cutter offers specialty and custom cuts.
I'm going to try and keep this within the rules :}
The biggest thing holding them back is they tend to more expensive and at times the numbers look different than what is expected on the market.
To do wide scale availability takes a lot of money to build inventory and marketing to build demand.
Then you have to charge a bit more to cover any additional weight loss from the rough and the added cutting time so they tend to be a bit on the high priced side.
De Beers years ago forced some cutters to cut some specialized cuts, none of which really took off even after spending millions in advertising.

MRBs are easier because there is just one faceting pattern and the facets are locked into specific locations on the diamond.
Plus there is well over a hundred years of research into cutting better rounds.

 

[diagem]

Hi lalala,
To answer that properly would take a book.
I also have a bit of conflict of interest as I have a specialty cut Asscher I designed and my partner/cutter offers specialty and custom cuts.
I'm going to try and keep this within the rules :}
The biggest thing holding them back is they tend to more expensive and at times the numbers look different than what is expected on the market.
To do wide scale availability takes a lot of money to build inventory and marketing to build demand.
Then you have to charge a bit more to cover any additional weight loss from the rough and the added cutting time so they tend to be a bit on the high priced side.
De Beers years ago forced some cutters to cut some specialized cuts, none of which really took off even after spending millions in advertising.

MRBs are easier because there is just one faceting pattern and the facets are locked into specific locations on the diamond.
Plus there is well over a hundred years of research into cutting better rounds.

Karl hit the nail spot on. The amount of time and energy that must be put into researching the optical combinations of potential proportions, facet placements and their angles causes such cuts to be extremely costly to bring to market.
Human nature then wants to compare prices on similar products (by shape and mainly the four C's). This causes a value disparity which unfortunately we as an industry have not yet discovered how to relay to the end consumer in a efficient manner.
The large picture..., in my years swimming in this light performance pool was very educational and allowed me to really understand Diamonds and their optical challenges. But unfortunately we are still far from the market acceptance on the value aspect it takes to bring such unique products.

 

[rockysalamander]

https://www.yadavjewelry.com/diamond/oval-diamond-1.28-carat-g-vs2-yd1592503

Too much mush.

Or this being a SI1 grade
https://www.adiamor.com/Diamonds/1....3359?q=rc&utm_source=rarecarat&utm_medium=cpc

You need a video to evaluate ovals. Don't discount SI1 and even 2. Depending on the nature and location of the inclusion they can offer great value. Several PS members "rock" eye-clean SI2.

Here are a few that are bigger and within your parameters (but I looked for eye-clean SI1 to get some size); But, inquire if these are eye-clean SI1.
https://www.jamesallen.com/loose-diamonds/oval-cut/1.20-carat-g-color-si1-clarity-sku-3638288, 8.72*6.13
https://www.jamesallen.com/loose-diamonds/oval-cut/1.20-carat-g-color-si1-clarity-sku-3705326, 8.14*6.02
https://www.jamesallen.com/loose-diamonds/oval-cut/1.20-carat-d-color-vs2-clarity-sku-3729930 {I'm on the fence with this one, I think the lighting is causing it to look grey straight-on} 7.73*5.74
https://enchanteddiamonds.com/v/1Z9Z30793 (good aset, may not be eyeclean, have to ask}, 8.15*6.06
https://www.goodoldgold.com/diamond...-F-VS2-diamond-stock-E31074-cert-US914487611D {this is EGL, but sold by a very reputable vendor. I would trust their evaluation and this is a great price. They may also agree to send to GIA.}, 7.44*5.61 mm

 

[lalala]

Makes sense. Thank you @Karl_K and @diagem! I appreciate the feedback.

 

[Rockdiamond]

Makes MRB's seem so easy... amazing how they have been "perfected" enough to compare to charts.

Is there just not enough interest in other cuts to spend this amount of time perfecting them?

If one were to dedicate hours, months (more than likely years), to perfect a cut, is the return worth it? Or are the standard cuts so ingrained (marketed) to consumers that a new cut or specialized cut is not worth the time because it will be overlooked?

Have serious marketing efforts ever been put into place for specialized cuts?

Sorry, OP not trying to thread-jack. A lot has been on my mind lately...

I have a different outlook on this from my esteemed colleagues.
To me the rough diamond is like a canvas and the best cutters are artists.
If we handcuffed the best cutters we'd loose diversity in each shape.
At the present time it's up to the dealer to select what they find beautiful and show their clients why - or a consumer to wade into the deep pool of mostly badly cut stones on the market and pick for themselves. Or use this amazing resource and get advice.
But the bottom line is that I don't thInk we can "legislatie" beauty in diamonds.
BTW - GIA is ( or at least was) trying to come up with fancy shape cut grades.

 

[lalala]

I have a different outlook on this from my esteemed colleagues.
To me the rough diamond is like a canvas and the best cutters are artists.
If we handcuffed the best cutters we'd loose diversity in each shape.
At the present time it's up to the dealer to select what they find beautiful and show their clients why - or a consumer to wade into the deep pool of mostly badly cut stones on the market and pick for themselves. Or use this amazing resource and get advice.
But the bottom line is that I don't thInk we can "legislatie" beauty in diamonds.
BTW - GIA is ( or at least was) trying to come up with fancy shape cut grades.

Thank you for a different perspective!

 

[Rhino]

Karl hit the nail spot on. The amount of time and energy that must be put into researching the optical combinations of potential proportions, facet placements and their angles causes such cuts to be extremely costly to bring to market.
Human nature then wants to compare prices on similar products (by shape and mainly the four C's). This causes a value disparity which unfortunately we as an industry have not yet discovered how to relay to the end consumer in a efficient manner.
The large picture..., in my years swimming in this light performance pool was very educational and allowed me to really understand Diamonds and their optical challenges. But unfortunately we are still far from the market acceptance on the value aspect it takes to bring such unique products.

I'm hoping DeBeers helps in this as they continue to roll out their black label collection. A collection which, at its foundation is built upon cutting for diamond optics. I've seen some of the cuts and some are outstanding. If they put serious marketing into the program and help *teach* what it is that makes them special it will help the market we're talking about.

 

[lalala]

I'm hoping DeBeers helps in this as they continue to roll out their black label collection. A collection which, at its foundation is built upon cutting for diamond optics. I've seen some of the cuts and some are outstanding. If they put serious marketing into the program and help *teach* what it is that makes them special it will help the market we're talking about.

See, I was unaware of their black label; just looked it up. It appears as though they gave arrows to ovals, cushions, squares and hearts.

Interesting. Now I question their marketing team..

ETA: I just pulled up YouTube and the video posted by Forevermark about their black label has about 1200 views and it's been up since January 2017. Ouch.

 

[Rhino]

The fundamental issue with proportions for ovals is that you're not getting the whole story even if one were to get the crown/pavilion angles and table/depth%. This is because those angles are generally only going to represent the angles at the belly and do not take into account the angles extending to the tips of the diamond, which by nature are cut very shallow. Dave Atlas' article is the best that can be offered based on traditional cutting methods but as Karl pointed out is not an end all/be all to ovals as even the best traditionally cut ovals will have less than desirable optical results.

 

[Rhino]

See, I was unaware of their black label; just looked it up. It appears as though they gave arrows to ovals, cushions, squares and hearts.

Interesting. Now I question their marketing team..

ETA: I just pulled up YouTube and the video posted by Forevermark about their black label has about 1200 views and it's been up since January 2017. Ouch.

LOL Youch is right!

 

[Rockdiamond]

Hey Jon
Marry Christmas!
You mention "diamond optics"
Is face up size part of the equation you have in mind?
Can we agree that each individual eye will appreciate different aspects associated with a diamonds optics?
In other words, it's not "good" or "bad" optics- it's just a word that describes the general appearance of a diamond.
Just as an example - imagine a shallow oval diamond cut from a makel that may look "bad" ina reflector but impressive in person. Especially in terms of size.
Beyond that remember that the piece of rough which became that oval could really not have been cut to anytime else that would have been economically feasible. In many cases such stones trade at larger discounts that stones described as ideal.
Net result is a larger diamond that costs less.
Not to say either buyer is "wrong" - it's a matter of priorities.

 

[Karl_K]

as even the best traditionally cut ovals will have less than desirable optical results.

Jon, we both know that is an exaggeration.
There are some very beautiful traditional cut ovals with fine optics on the market.

 

[Karl_K]

Hey Jon
Marry Christmas!
You mention "diamond optics"
Is face up size part of the equation you have in mind?
Can we agree that each individual eye will appreciate different aspects associated with a diamonds optics?
In other words, it's not "good" or "bad" optics- it's just a word that describes the general appearance of a diamond.
Just as an example - imagine a shallow oval diamond cut from a makel that may look "bad" ina reflector but impressive in person. Especially in terms of size.
Beyond that remember that the piece of rough which became that oval could really not have been cut to anytime else that would have been economically feasible. In many cases such stones trade at larger discounts that stones described as ideal.
Net result is a larger diamond that costs less.
Not to say either buyer is "wrong" - it's a matter of priorities.

The reflector scopes assume a very close viewing distance, there are shallow ovals that show to much blue in ASET that are beautiful diamonds.
Some will be a bit dark up close at 8 inches in person, some not because a person isn't a blue disk. Many more will rock in a pendant or ear rings and some will just plain be kinda yucky.
There are certainly bad and good optics. The definition of what is good and bad is where the questions comes into play.

 

[diamondseeker2006]

I've seen a good many ovals posted here over time, and I honestly haven't seen many good ASET images. Seeing blue wouldn't concern me as much as seeing all the white (which is leakage when the stone is on a white background).

@mdl0216, the pros Unfortunately aren't allowed to post examples of great stones for sale. You could sift through the ones on James Allen and ask for ASET images on three of them (the max they will allow you to request at one time). The first two rockysalamander posted are worth looking at, but that GOG stone is apparently not in-house. But honestly, if she hasn't specifically asked for an oval, I'd go for the round as we can definitely help you find a great round.

 

[Rhino]

Greetings my brothers.

Thoughts between the lines.

Hey Jon
Marry Christmas!
You mention "diamond optics"
Is face up size part of the equation you have in mind?

No. Face up size has absolutely nothing to do with the optical properties of diamond. Namely brightness, fire, sparkle and contrast. There are many cases of smaller diamonds being way more beautiful than larger diamonds due to their ability to reflect and refract light. The Octavia would be a great example that demonstrates this too.

Can we agree that each individual eye will appreciate different aspects associated with a diamonds optics?
In other words, it's not "good" or "bad" optics- it's just a word that describes the general appearance of a diamond.

Not when it's greater than 9 out of 10 people.

Just as an example - imagine a shallow oval diamond cut from a makel that may look "bad" ina reflector but impressive in person. Especially in terms of size.
Beyond that remember that the piece of rough which became that oval could really not have been cut to anytime else that would have been economically feasible. In many cases such stones trade at larger discounts that stones described as ideal.
Net result is a larger diamond that costs less.
Not to say either buyer is "wrong" - it's a matter of priorities.

True dat. Take your same example though and apply it to rounds (or any shape for that matter). Shallow cut rounds look bigger ... no argument and to the consumer there is a portion of the market who will take a shallow, extremely leaky round that looks bigger over a more beautifully cut Ideal round or H&A that looks smaller. To each their own. My aim was to provide the latter in a cut that leaks light like a sieve and to alter what always bothered me about the traditional cutting methods of this shape. Whereas once the consumer had absolutely no choice now they have a choice. Choice is good no?

Jon, we both know that is an exaggeration.
There are some very beautiful traditional cut ovals with fine optics on the market.

LOL ... well you're speaking in relative terms my friend. That's like saying not all AGS 10's are that bad. Bottom line is this ...
I don't like color absorption in these cuts. I'd rather have a diamond face up whiter.
I don't like bowties. #byebyebowtie
And you know I, just like you, don't like light leakage. I want to see brightness, fire & sparkle where there is generally always mush.

You and I think alike in these matters Karl. I know you understand my thinking completely as well as our friends at AGS and the science backing their system.

Hope this finds you all in good spirits.

Peace,
Rhino