21 replies to this topic

[Martinicus]

HI there,

I am in the last, most confused, throes of buying a diamond for a six prong platinum setting, and am trying to decide between going for a 0.79 VS2 F colour diamond or a 0.86 SI1 G colour diamond for around the same price. Can anyone offer me any advice to make this decision somewhat easier? In both cases I am looking at a GIA cut grade of 'Ideal', with 'Excellent' polish and symmetry.

Many thanks in advance for any assistance.

[barry]

In terms of physical size, color, or clarity you will not see any visual difference in the face up position.

The key here is light performance and the diamonds refraction of light up through the top of the stone to your eye which may differ depending on the interaction of the facet angles. Is such information available from the Vendor(s) on these diamonds?

BTW, GIA does not give a Cut Grade of "Ideal" on the round brilliant shape. This term is used by the AGS laboratory for its top Cut Grade whereas GIA uses the term "Excellent".

[Martinicus]

Sorry, 'Excellent' is what I meant. The vendor I was looking at is 'Blue Nile' as they are one of the few I found that deliver to the UK - they don't seem to have any information with regards to colour performance - is this a subjective judgement? Is it not covered by the 'polish/symmetry/cut' parameters?

With the Colour, I don't want to have it look visibly yellowish when set in a platinum band. With Clarity, I don't really care about inclusions so long as they aren't visible to a fairly casual examination (ie, don't mind at all what it looks like under magnification). With Cut, my research on this site and others seem to strongly suggest that you should max out the cut as it is the strongest indication of fire, brilliance and all around sparkliness. With all of the above factored in, I don't want to spend much more than around US$5000. When factoring in VAT (17.5%), and around $800 for a platinum band, it probably leaves me with around $3300 for the diamond itself. So for that kind of money, I was looking to get the biggest, most brilliant diamond I can find without worrying too much about parameters that aren't apparent to lay people.

The above had kind of led me to G, SI1, 0.80, with Excellent cut/polish/symmetry - is that about right?

Thanks

[LittleSharon]

Martinicus, on Thursday, Aug 16 2007, 05:23 AM, said:

Sorry, 'Excellent' is what I meant. The vendor I was looking at is 'Blue Nile' as they are one of the few I found that deliver to the UK - they don't seem to have any information with regards to colour performance - is this a subjective judgement? Is it not covered by the 'polish/symmetry/cut' parameters?

With the Colour, I don't want to have it look visibly yellowish when set in a platinum band. With Clarity, I don't really care about inclusions so long as they aren't visible to a fairly casual examination (ie, don't mind at all what it looks like under magnification). With Cut, my research on this site and others seem to strongly suggest that you should max out the cut as it is the strongest indication of fire, brilliance and all around sparkliness. With all of the above factored in, I don't want to spend much more than around US$5000. When factoring in VAT (17.5%), and around $800 for a platinum band, it probably leaves me with around $3300 for the diamond itself. So for that kind of money, I was looking to get the biggest, most brilliant diamond I can find without worrying too much about parameters that aren't apparent to lay people.

The above had kind of led me to G, SI1, 0.80, with Excellent cut/polish/symmetry - is that about right?

Thanks

I think your logic seems sound, but will leave the specific advice to the experts here. Im imagining that you could even go down to H and SI2 if the cut was good enough to give the diamond its fine `motor` which is the most important thing we are told!!!!

What I am dying to know is that if everyone recognises that the angle of the facets and their relationship to each other (mirrors/ windows etc) is what gives the diamond its edge, being light reflection, scintillation, fire, then why is this not the most important part of any certificate????

Why doesnt the diamond industry recognise that this should be part of all reports on the diamonds being analysed. Then consumers could feel more confident that they were buying the best they can for their money.

I cant understand that this aspect of diamond buying....the cut.....is the most important part, but, is the only thing not on the reports that we rely on to help us choose????? And apparently the cut in itself is not enough to determine the amount of fire and scintillation that the diamond will produce???

[barry]

Martinicus, on Thursday, Aug 16 2007, 06:23 AM, said:

Sorry, 'Excellent' is what I meant. The vendor I was looking at is 'Blue Nile' as they are one of the few I found that deliver to the UK - they don't seem to have any information with regards to colour performance - is this a subjective judgement? Is it not covered by the 'polish/symmetry/cut' parameters?

With the Colour, I don't want to have it look visibly yellowish when set in a platinum band. With Clarity, I don't really care about inclusions so long as they aren't visible to a fairly casual examination (ie, don't mind at all what it looks like under magnification). With Cut, my research on this site and others seem to strongly suggest that you should max out the cut as it is the strongest indication of fire, brilliance and all around sparkliness. With all of the above factored in, I don't want to spend much more than around US$5000. When factoring in VAT (17.5%), and around $800 for a platinum band, it probably leaves me with around $3300 for the diamond itself. So for that kind of money, I was looking to get the biggest, most brilliant diamond I can find without worrying too much about parameters that aren't apparent to lay people.

The above had kind of led me to G, SI1, 0.80, with Excellent cut/polish/symmetry - is that about right?

Thanks

Just about all of the Internet Stateside Diamond Vendors ship to the U.K.

F-G color in the Excellent to Ideal Cut Grade quality you prefer will not look "yellowish" at all.

Insofar as evaluating the brilliance, dispersion, and sparkle of the diamonds, BN does not provide this kind of information.

[denverappraiser]

LittleSharon, on Thursday, Aug 16 2007, 07:39 AM, said:

Why doesnt the diamond industry recognise that this should be part of all reports on the diamonds being analysed. Then consumers could feel more confident that they were buying the best they can for their money.

Sharon,

Despite it’s reputation, the ‘diamond industry’ is not some monolithic company or group of that acts in one direction nor does everyone in it act in the best interest of consumers. It's a whole bunch of intertwined and competing companies. The simplest answer to why the labs don’t include more useful and more consistent data for shoppers on their reports is because their customers don’t wish them to. Some lab reports are more useful than others in this regard and most labs have a variety of formats available that contain different information but in almost all cases, the lab is selling services to dealers, not to consumers. You are not the intended beneficiary, the dealer is, and their purpose in ordering the report was to get a document that would cause that particular diamond to sell better.

Neil

Edited by denverappraiser, 16 August 2007 - 04:26 AM.

[LittleSharon]

denverappraiser, on Thursday, Aug 16 2007, 07:20 AM, said:

LittleSharon, on Thursday, Aug 16 2007, 07:39 AM, said:

Why doesnt the diamond industry recognise that this should be part of all reports on the diamonds being analysed. Then consumers could feel more confident that they were buying the best they can for their money.

Sharon,

Despite it’s reputation, the ‘diamond industry’ is not some monolithic company or group of that acts in one direction nor does everyone in it act in the best interest of consumers. It's a whole bunch of intertwined and competing companies. The simplest answer to why the labs don’t include more useful and more consistent data for shoppers on their reports is because their customers don’t wish them to. Some lab reports are more useful than others in this regard and most labs have a variety of formats available that contain different information but in almost all cases, the lab is selling services to dealers, not to consumers. You are not the intended beneficiary, the dealer is, and their purpose in ordering the report was to get a document that would cause that particular diamond to sell better.

Neil

Neil, I really should have worked that out myself!!!!!

So rephrase question......why is it not in the sellers interests to have the report target this aspect of the diamond, which incidentally is the most important part of the diamond......is it because most diamonds would not do well with the fire/ light performance test (assuming that there was a recognised test for arguments sake).

I have noticed that this lack in the information market is being jumped on by the branded diamond cutseg H&A and report systems like Light scope etc. So obviously as consumer awareness grows this lack in the reporting will have to be addressed??? Opinions......And any advice for consumers not able to get Lightscope tests etc.....is it so bad to rely on ones eyesite????? Or are we all buying cars with no regard to looking under the bonnet, so to speak?

[denverappraiser]

Some labs, especially AGSL, report cutting information and the fact that they do is the reason most people use them. The choice of lab is made based on what will make that particular stone look best. The vast majority of stones sent to AGSL are round and princess cuts that are expected to get a ‘0’ light performance and were sent there for this reason. Why would anyone send a stone to them if they know going in that it will get a poor score when they could send it somewhere else or simply order a different format report and either be ranked on a different scale or simply not get ranked at all? EGL-USA and GCAL offer ‘hearts and arrows’ grading reports that serve the same general purpose. An H&A report will only be ordered for a stone that meets the lab’s standards for H&A (lab standards is a whole different topic and they decidedly don’t agree).

Only 10% of the diamonds will be in the top 10% cut wise. This may seem obvious but the dealers still need to sell those other 90%. That, for example, is why the range of the GIA scale is so big for ‘excellent’ cutting on round stones.

As a consumer, your eyes are the very best way to shop although it’s a little hard to train your benchmark of what is good and what is excellent and a bit of practice is very helpful. Make sure to examine the stone in a variety of different lighting environments because it makes a difference and most jewelry stores are designed with lighting that would make a dirt clod look good. Reflectors like the lightscope, ASET and idealscope are handy little tools and some are pretty inexpensive and can be very helpful with a little bit of practice and it doesn’t require much on the jewelers part. Idealscopes are an Aussie product by the way, http://www.ideal-scope.com

Neil

Edited by denverappraiser, 16 August 2007 - 07:00 AM.

[barry]

GIA's Cut Grade system for the round brilliant diamond shape incorporates light performance in its assessment of Cut Quality. Their explanation of their methodology and arrival at their different classifications can be found on their website: gia.edu

AGS Cut Grade also incorporates light performance into its Cut Grade system and is heavily based on ray tracing, which has its limitations.

Both Labs Cut Grade systems have their critics, which is not surprising in view of the fact that visual perception of diamond beauty is exceedingly complex and involves a host of variables that are difficult to scientifically control.

Hence the introduction of outside assessor technologies such as the Idealscope, Brilliancescope, Isee2, Imagem, et al., which provide information on light performance.

Definitely a work in progress but certainly preferable to buying a diamond just based off a lab grading report.

[Martinicus]

I had briefly considered getting an 'idealscope' to be able to make these kinds of judgement calls myself, but it seems like over-kill considering I am only really planning on buying one diamond. However, I do want to make sure it is the _right_ diamond. I was in a jewelry shop a couple of days ago looking at some diamonds and to be honest, they seemed extraordinarily lifeless - no fire at all, despite having very high cut/symmetry/polish ratings - and a massive price.

I don't have a huge amount of faith in local suppliers...but maybe what I need to do is buy an ideal-scope, go around to various suppliers to get an idea of how the thing works, then buy something from the internet and use the ideal-scope to confirm that it matches expectations?

[denverappraiser]

Martinicus, on Thursday, Aug 16 2007, 09:32 AM, said:

I had briefly considered getting an 'idealscope' to be able to make these kinds of judgement calls myself, but it seems like over-kill considering I am only really planning on buying one diamond. However, I do want to make sure it is the _right_ diamond. I was in a jewelry shop a couple of days ago looking at some diamonds and to be honest, they seemed extraordinarily lifeless - no fire at all, despite having very high cut/symmetry/polish ratings - and a massive price.

I don't have a huge amount of faith in local suppliers...but maybe what I need to do is buy an ideal-scope, go around to various suppliers to get an idea of how the thing works, then buy something from the internet and use the ideal-scope to confirm that it matches expectations?

Don’t confuse symmetry and polish ratings with cut grading. These are not the same. You can have an Excellent/Excellent symmetry and polish with a dud stone. I agree with Barry that scientifically defining beauty is a Sisyphean task but any stone given the top grade by either GIA or AGS will not be described as dull and lifeless in any sensible lighting environment. There are differences between the stone and there is a fair amount of argument over what is ‘best’ but this is all in the details. All will be at least 'pretty good'.

Visit some of the high end type shoppes that sell the branded goods like Hearts on Fire or a Kaplan and see if you can tell the difference. Even if you don't end up buying one, it's helpful in training your eyes on what to look for.

Idealscopes and their various clones have an interesting side effect. It identifies YOU as an Internet educated customer. It means that you're at least moderately serious since you bought the thing, it means that you are planning to be picky about your purchase and it means that you are going to be price and information conscious (because of the Internet connection). The stores that are good at selling to such customers are exactly the ones you want anyway so you actually gain quite a bit by pulling an IS out of your purse before you look at a single stone. It's helpful to be skilled at handling stones with a pair of tweezers before you walk in for similar reasons.

Special note: Do ask them permission before you use your own tools, tweezers, loupe or anything else. Show it to them first if they would like look at it and give them a brief explanation of what it is if they don't already know. If they have one, by all means use theirs instead of yours. Stores have legitimate security concerns about this sort of thing.

Neil

Edited by denverappraiser, 16 August 2007 - 08:32 AM.

[LittleSharon]

Another thing that is interesting, is that some stones are cut for brilliance and others are cut for fire. Somehow that really fascinates me. Its such a science!

I will look into that Lightscope!

BTW, I dont go to any shops, my h. brings them home. Often I find it hard to even tell if they are real, since once he brought me home a fake one that was set!!! Well, that fake one has had more compliments than you would believe......but it is not getting him off the hook either!

[10X]

If you are looking for an "Ideal" cut diamond with excellent light return, why not just choose an AGS Ideal stone or better yet choose from the vendors that provide you actual IdealScope and/or BrillianceScope information?

[LittleSharon]

10X, on Thursday, Aug 16 2007, 01:16 PM, said:

If you are looking for an "Ideal" cut diamond with excellent light return, why not just choose an AGS Ideal stone or better yet choose from the vendors that provide you actual IdealScope and/or BrillianceScope information?

Well, untill now, I didnt realise these things even existed!!!! You see in Aust. I have never heard anyone talk about the cut, except for situations where the diamond has been cut to look bigger from the top, therefore making it a `bad` cut. We sort of assume that if it is not a bad cut then it is a good cut!!!!!

But I have never been exposed to the idea that diamonds can have different aspects to their beauty, or that each angle has a role in the end result. I didnt realise that there is a science to it.

I am on a budget and I know I am looking at the low end for my carat size......but my sister actually has an unlimmited budget, and I know that she lately bought 2 * 2 c.diamond earrings without much regard to cut (only color and clarity). So here in Australia it is somthing that is given token coverage, meaning that sellers will tell you its a good cut, and that will be the end of the conversation.

Ps. sorry to have hijacked this thread, but hopefully the conversation is useful to the original poster!

[Martinicus]

10X, on Thursday, Aug 16 2007, 01:16 PM, said:

If you are looking for an "Ideal" cut diamond with excellent light return, why not just choose an AGS Ideal stone or better yet choose from the vendors that provide you actual IdealScope and/or BrillianceScope information?

Which vendors offer this kind of information? I've only really been looking at Blue Nile as my online vendor due to the fact that they have a .uk, and the fact that I've researched the background of the company enough to be sure that I'm unlikely to receive a lump of glass. One thing I really don't like about them is their selection of six prong white gold/platinum settings - they only have one! And unfortunately, it is horrible.

Can anybody reccomend some other trustworthy reliable vendors with a decent selection of six prong platinum settings who also offer some indication of 'light performance'? I want maximum sparkle factor. Somewhere on the idealscope website were a couple of animated gifs which demonstrated the difference between a diamond with high scintillation and low scintillation - and I realised that this was what was missing from the diamonds I have viewed locally (with their inflated prices and hard sell tactics).

Thanks again for all of your assistance!

[denverappraiser]

Megan and Barry, both of whom have participated in this thread are with excellent companies that I have no doubt would be happy to work with a customer in the UK. You can find others by looking in the 'find online jeweler' database at the top of the page or by looking through the other threads for comments from people that seem like you can relate to. All of the jewelers have a 'verified jeweler' tag below their pictures and a link at the bottom of each post to their websites.

Neil

[shadow12345]

For the UK, cooldiamonds served me pretty well. They are online and also have a shop - where *all* of the diamonds on their website are kept - in Hatton Garden (in the City in London).

You can buy online off certificate, or go down and talk to them, still buying at internet prices. They are pretty flexible and can custom make/change their bands to suit.

If you are in London or the South wandering around Hatton Garden is a great idea, every shop sells only diamonds, and because the competition is so fierce they all sell close to wholesale prices (this translates to about 50% of high street prices for, generally, much nicer diamonds).

The Lanes in Brighton is also quite good, and there is an area in Birmingham as well, but I think Hatton Garden is the cheapest and best place for diamonds.

If you do import something from an american website you may have to sort something out with the tax office...??

[Martinicus]

shadow12345, on Sunday, Aug 19 2007, 12:21 PM, said:

For the UK, cooldiamonds served me pretty well. They are online and also have a shop - where *all* of the diamonds on their website are kept - in Hatton Garden (in the City in London).

You can buy online off certificate, or go down and talk to them, still buying at internet prices. They are pretty flexible and can custom make/change their bands to suit.

If you are in London or the South wandering around Hatton Garden is a great idea, every shop sells only diamonds, and because the competition is so fierce they all sell close to wholesale prices (this translates to about 50% of high street prices for, generally, much nicer diamonds).

The Lanes in Brighton is also quite good, and there is an area in Birmingham as well, but I think Hatton Garden is the cheapest and best place for diamonds.

If you do import something from an american website you may have to sort something out with the tax office...??

Thanks a million for the link, it seems that even with VAT included, the prices are comparable with American sites! I will definitely think about heading down to London to check out Hatton Garden.

Any reccomendations on how to compare the light performance of two diamonds with identical certificates (without visual inspection - I doubt I will be able to develop the ability to make meaningful visual judgement calls in time to purchase!)? Is it a 'simple' matter of selecting the one closest to the Tolkowsky ideal or a high rating on the Holloway Cut Advisor ?

Thanks!

[barry]

Martin;

Two points:

1. The Towlkowsky Ideal encompasses a range in which it has been demonstrated that there is no absolute uniformity in light performance and that variance, sometimes significant, does exist.

2. The HCA, by the clear advocacy of its inventor is not a "Pick" tool but a "Reject" tool which can eliminate a large segment of poor to mediocre cut diamonds from purchase consideration. The HCA formula evaluates only 17 of the 58 facets that comprise the round brilliant shape and the 41 facets that are not analyzed can critically affect the face up appearance and sparkle of the diamond, depending on their facet angle, size, and proper alignment.

[JohnQuixote]

barry, on Tuesday, Aug 21 2007, 07:13 PM, said:

Martin;

Two points:

1. The Tolkowsky Ideal encompasses a range in which it has been demonstrated that there is no absolute uniformity in light performance and that variance, sometimes significant, does exist.

2. The HCA, by the clear advocacy of its inventor is not a "Pick" tool but a "Reject" tool which can eliminate a large segment of poor to mediocre cut diamonds from purchase consideration. The HCA formula evaluates only 17 of the 58 facets that comprise the round brilliant shape and the 41 facets that are not analyzed can critically affect the face up appearance and sparkle of the diamond, depending on their facet angle, size, and proper alignment.

3. A diamond with 'ideal' light performance from the AGSL has been judged based on the output of all facets combined. This is a good pedigree if you like. Be aware that there is a range of different 'looks' even inside that pedigree.

4. When buying sight-unseen there is no substitute for a professional who actually has the stone in-hand (some don't ), who will provide photos and in-house light performance assessment and - most importantly - you feel is trustworthy enough to be an advocate in finding a superior stone for you. This may be a seller, an appraiser or combo of the two. It never hurts to have good return periods and long-term policies like trade-in/trade-up.

5. Louping and scoping a diamond in live shopping situations is cool - those are the only views you see online (and usually never in stores) so it's fair to compare - but remember your eyes are your most useful tool. You need to use them to view a diamond in several different lighting conditions, not just under jewelry store lights.

6. One day I hope my beard looks as distinguished as Barry's.

Edited by JohnQuixote, 22 August 2007 - 07:19 AM.