How can a consumer select a fancy shape?

[Stephan]

Date: 3/26/2010 9:33:06 AM
Author: Karl_K

Date: 3/26/2010 9:04:19 AM
Author: oldminer
No doubt many fine looking fancy shapes have deeper total depth percentages than in the AGA charts and look excellent, but they generally look smaller than alternative choices which weigh the same and may look larger for the same money.

The above statement is not true.
In step cuts depth is not proportional to spread.
It is also true in many fancies.

Without the word ''generally'', the statement would be false.

 

[Paul-Antwerp]

Date: 3/26/2010 9:41:51 AM
Author: QueenMum

Date: 3/26/2010 9:33:06 AM
Author: Karl_K

Date: 3/26/2010 9:04:19 AM
Author: oldminer
No doubt many fine looking fancy shapes have deeper total depth percentages than in the AGA charts and look excellent, but they generally look smaller than alternative choices which weigh the same and may look larger for the same money.

The above statement is not true.
In step cuts depth is not proportional to spread.
It is also true in many fancies.

Without the word ''generally'', the statement would be false.

The statement is false. Period. Using ''generally'' and ''may'' do not make it less true.

Even considering that the AGA-charts are apparently a craftsmanship screening tool (news to me), there is no automatic relationship between depth and spread in a fancy shape, and there is no relation between this and craftsmanship.

Then again, this is taking us away from the original topic again.

Live long,

 

[ChunkyCushionLover]

Date: 3/26/2010 9:01:35 AM
Author: Karl_K

Date: 3/26/2010 7:16:16 AM
Author: Paul-Antwerp
Going back to the original topic, I see a lot of agreement with the fact that a consumer is facing an impossible task to select a few candidates from the virtual list.
Live long,

Paul, well some consumers had better systems than others on figuring out which stones to call in, my track record with asschers was very good.
Part of the reason was being able to recognize a couple different cutters work by the numbers.
Your princess cuts could be picked out of a virtual list in the same way once they were discovered.
There were and are a couple cutters that have a much better chance of being excellent asschers than others on the list, there is two that was guaranteed not to be acceptable that could be sorted out the same way.
Sometimes I knew a stone was not going to be acceptable and it was frustrating when it was insisted on being called in because it was a couple hundred cheaper.
So you are right sorting by price is a bad move, but calling in the most expensive on the list can be just as bad.

That your vendor knows how to pick the right supplier/cutter is important when calling diamonds in.

I agree with Karl, for some styles of cushion cuts like the antique faceted 8 main and modern 8 main, I have a very good system for figuring out if a stone came from one of three or four vendors that were known to be producing diamonds with light performance in mind over weight retention. Further within those vendors I can use numerical ranges to narrow down with a low rejection rate (depends on your absolute standard) using only Depth, Table, LW Ratio and Girdle thickness the best performers available in that cutting style. Sure false positives can and do occur, and false negatives as well (but usually not very many if your standards are really high) but the numerical methods work for some of the "specialist" PS vendors and they would work for anyone.

I know Rhino tries to as efficiently as possible to select certain factories for fancies from virtual lists and also in screening selections from those factories based on the numbers first. This is very necessary for his business model as GOG strives to offer the best in cut in each fancy type outline and if found offer a lifetime upgrade policy on the stone. This doesn't always work out and with some shapes is a lot more difficult to do, especially if you have extremely high standards as Jon does. One only has to look on his website at the diamonds still for sale with only 30 day policies to see all the ones he called in that did not meet his standards.

Rhino's profit margin and really any vendors profit margin depends in part on having a low rejection rate for the virtual stones called in. The markup is quite similar whether he has to call in 1 stone or 10 stones to get a certain look or performance level for a customer. For any particular shapes where he can't find a factory with good enough consistancy for a particular cut and outline shape this may lead to the developed of his own branded line (AVC or OEC for example) with pretty consistant cut standards.

I don't see any trademember here explicitly mentioning their selection criteria by the numbers on a particular fancy shape for two obvious reasons:

1) Their selection criteria gives them a competitive advantage over other vendors and if known could lead to knowing who their preferred suppliers were.
2) The ranges being proposed would be constantly scrutinized like the AGA system and others would be constantly trying to tear down those ranges based on providing examples of false positive or negatives.

 

[Lula]

Date: 3/26/2010 9:59:30 AM
Author: ChunkyCushionLover

Date: 3/26/2010 9:01:35 AM

Author: Karl_K

Date: 3/26/2010 7:16:16 AM

Author: Paul-Antwerp

Going back to the original topic, I see a lot of agreement with the fact that a consumer is facing an impossible task to select a few candidates from the virtual list.

Live long,

Paul, well some consumers had better systems than others on figuring out which stones to call in, my track record with asschers was very good.

Part of the reason was being able to recognize a couple different cutters work by the numbers.

Your princess cuts could be picked out of a virtual list in the same way once they were discovered.

There were and are a couple cutters that have a much better chance of being excellent asschers than others on the list, there is two that was guaranteed not to be acceptable that could be sorted out the same way.

Sometimes I knew a stone was not going to be acceptable and it was frustrating when it was insisted on being called in because it was a couple hundred cheaper.

So you are right sorting by price is a bad move, but calling in the most expensive on the list can be just as bad.


That your vendor knows how to pick the right supplier/cutter is important when calling diamonds in.

I agree with Karl, for some styles of cushion cuts like the antique faceted 8 main and modern 8 main, I have a very good system for figuring out if a stone came from one of three or four vendors that were known to be producing diamonds with light performance in mind over weight retention. Further within those vendors I can use numerical ranges to narrow down with a low rejection rate (depends on your absolute standard) using only Depth, Table, LW Ratio and Girdle thickness the best performers available in that cutting style. Sure false positives can and do occur, and false negatives as well (but usually not very many if your standards are really high) but the numerical methods work for some of the 'specialist' PS vendors and they would work for anyone.


I know Rhino tries to as efficiently as possible to select certain factories for fancies from virtual lists and also in screening selections from those factories based on the numbers first. This is very necessary for his business model as GOG strives to offer the best in cut in each fancy type outline and if found offer a lifetime upgrade policy on the stone. This doesn't always work out and with some shapes is a lot more difficult to do, especially if you have extremely high standards as Jon does. One only has to look on his website at the diamonds still for sale with only 30 day policies to see all the ones he called in that did not meet his standards.



Rhino's profit margin and really any vendors profit margin depends in part on having a low rejection rate for the virtual stones called in. The markup is quite similar whether he has to call in 1 stone or 10 stones to get a certain look or performance level for a customer. For any particular shapes where he can't find a factory with good enough consistancy for a particular cut and outline shape this may lead to the developed of his own branded line (AVC or OEC for example) with pretty consistant cut standards.


I don't see any trademember here explicitly mentioning their selection criteria by the numbers on a particular fancy shape for two obvious reasons:


1) Their selection criteria gives them a competitive advantage over other vendors and if known could lead to knowing who their preferred suppliers were.

2) The ranges being proposed would be constantly scrutinized like the AGA system and others would be constantly trying to tear down those ranges based on providing examples of false positive or negatives.

Great posts, CCL, and Karl.

Reading a bit between the lines -- but not too much I hope -- of what both of you are saying, it seems that the added cost to selecting a good fancy cut may not be in the actual "cost" of the stone itself as it exists on the virtual list, but rather the "cost" one is willing to pay for the expertise in selecting a good fancy cut.

As I see it, to select a good fancy cut, a consumer has just a few options:

1. Spend untold hours learning about fancy cuts, viewing fancy cuts in person, becoming a cut geek -- the "Karl K" model. Not an option for me, and most other consumers.

2. Rely on help from prosumers on this forum. An imperfect system with fancies, as has been discussed, and made more imperfect by the tendency of consumers to treat diamonds as fungible goods. So when searching through a virtual list one assumes is fungible, cost becomes the driving force.

3. Pay someone for their expertise. This goes back to the "trust your vendor" concept, which is tantamount to treason on PS, but go back and read Neil Beatty (denverappraiser's) post. He makes some good points.

4. Consider branded cuts that offer consistency from stone to stone (but check carefully into what the brand standards are and the credentials of those behind the brand). There are a few branded fancy cuts; in my opinion, there could be more. My suspicion is consumers lured by the siren call of the virtual lists and their false promise of getting "something for nothing" relegates this option to last place.

 

[ChunkyCushionLover]

Date: 3/26/2010 9:56:19 AM
Author: Paul-Antwerp

Date: 3/26/2010 9:41:51 AM
Author: QueenMum

Date: 3/26/2010 9:33:06 AM
Author: Karl_K

Date: 3/26/2010 9:04:19 AM
Author: oldminer
No doubt many fine looking fancy shapes have deeper total depth percentages than in the AGA charts and look excellent, but they generally look smaller than alternative choices which weigh the same and may look larger for the same money.

The above statement is not true.
In step cuts depth is not proportional to spread.
It is also true in many fancies.

Without the word 'generally', the statement would be false.

The statement is false. Period. Using 'generally' and 'may' do not make it less true.

Even considering that the AGA-charts are apparently a craftsmanship screening tool (news to me), there is no automatic relationship between depth and spread in a fancy shape, and there is no relation between this and craftsmanship.

Then again, this is taking us away from the original topic again.

Live long,

I don't think thats really fair to OldMiner or really to education in general.

There defintely is a direct but not automatic correlation between depth and spread it certainly isn't an inverse correlation

.
However the problem is that it can only be applied definitively within the same outline shape and CUTTING STYLE.
It is a lot easier to apply this correlation to brilliant cuts, for step cuts the design has a lot more variables that can be changed.

I can see where OldMiner has selected for Classical Emerald Cuts to try to choose ones with taller crowns and also ones that don't have overly steep pavillions (from the depth %). This is definitely not perfect because the height of each step is important as well. Unfortuantely the charts have penalized the best class of ECs (light performance wise) with even taller crowns like 15-25% and that doesn't just apply to the Octavia. Perhaps well cut examples of those really tall crown varieties weren't available when he created the charts?

The example of Karl's Octavia comes up and it diverges from spread/depth correlations from any classical Square Emerald Cut because of its tall crown and successively steep narrow steps.
While most ECs have flatter tops with large tables , the octavia is built more like a pyramid in the crown with the top step or table being small.

I am not sure (I've never seen one Kenny maybe you can answer) but the perception of spread of an Octavia should be different than a large tabled square emerald cut with a more shallow crown.
The metric of spread is taken using the proportions of the girdle outline but roughly 1/3 of the Octavia's height is above this girdle plain and this has to look different (probably smaller) than diamonds with the same spread and a much larger table.

 

[ChunkyCushionLover]

Diagram showing the difference.

 

[kenny]

Date: 3/26/2010 10:49:58 AM
The example of Karl's Octavia comes up and it diverges from spread/depth correlations from any classical Square Emerald Cut because of its tall crown and successively steep narrow steps.
While most ECs have flatter tops with large tables , the octavia is built more like a pyramid in the crown with the top step or table being small.

I am not sure (I've never seen one Kenny maybe you can answer) but the perception of spread of an Octavia should be different than a large tabled square emerald cut with a more shallow crown.
The metric of spread is taken using the proportions of the girdle outline but roughly 1/3 of the Octavia's height is above this girdle plain and this has to look different (probably smaller) than diamonds with the same spread and a much larger table.

Karl, didn't you once say the spread of the Octavia is similar to generic asschers?

CCL, you mentioned "perception of spread".
I'm not sure what you mean, because spread is not based on perception.
Rather, it is an absolute thing based on two measurements.
It could be expressed mathematically as width (or more accurately area) over weight, because for a given weight if the width goes up the spread goes up.

That said, if you are introducing a new concept that's fine.
Here is a generic asscher and an Octavia photographed side by side.
Since the asscher on the left is almost double the carat weight of the Octavia so you could argue this pic is worthless for comparing spread, but it is useful for discussing perception of spread.
It shows the look of both, side by side.
The asscher has long bars and a big table.
You could argue this gives it a more spready look or feeling.

 

[oldminer]

I purposely use the word "generally" or the word "may" because the statements are not 100% true in every case and we all know it. To say that they are untrue statements when they are absolutely properly qualified statments is over the top and not an honest way to approach a dialogue in hopes of ever reaching a fair conclusion. Everyone here knows that the Octavia was not around during the preriod where the charts were created. At the same time, no one sold Asscher cuts although a few old ones floated around. No charts were ever made for these shapes because they are special cases which are designed with high depth and sold to people who want the "look" of these particular step cuts.

Neither is made with wide tables, very thin or very thick girdles purposely. If such a diamond were shown as a potential purchase there would be plenty of advice given about these features not being "perfect" in the craftsmanship of such a diamond even without an AGA grade for that shape. There are some universal rules about diamonds which don''t change regardless of the shape. The design of most new cuts take into account the durability aspects of diamonds and they are cut so as not to incur criticism of this type. I see that as a big improvement over the status quo of years before. If no one called attention to this situation, there would be far more temptation to save a bit more weight and cut with a few more nearly hidden problems.

All I see are better informed consumers who know a bit more how to shop for diamonds thanks to the systematic way I approached their buying and learning problems even before the Internet existed for most of us. You can use the relatively small number of diamonds which might not work in the AGA system to show it is imperfect, but you can''t use the majority of diamonds because they generally (my favorite qualifier) do fit the system nicely. BTW "nicely" is another qualifier as it is not saying the system is 100% correct. I do think it helps people shop safely. It may limit choice a bit, but there are so many to choose from that everyone can find a diamond who wishes to buy one.

 

[ChunkyCushionLover]

Date: 3/26/2010 11:31:53 AM
Author: kenny

Date: 3/26/2010 10:49:58 AM
The example of Karl's Octavia comes up and it diverges from spread/depth correlations from any classical Square Emerald Cut because of its tall crown and successively steep narrow steps.
While most ECs have flatter tops with large tables , the octavia is built more like a pyramid in the crown with the top step or table being small.

I am not sure (I've never seen one Kenny maybe you can answer) but the perception of spread of an Octavia should be different than a large tabled square emerald cut with a more shallow crown.
The metric of spread is taken using the proportions of the girdle outline but roughly 1/3 of the Octavia's height is above this girdle plain and this has to look different (probably smaller) than diamonds with the same spread and a much larger table.

Karl, didn't you once say the spread of the Octavia is similar to generic asschers?

CCL, you mentioned 'perception of spread'.
I'm not sure what you mean, because spread is not based on perception.
Rather, it is an absolute thing based on two measurements.
It could be expressed mathematically as width over weight, because for a given weight if the width goes up the spread goes up.

That said, if you are introducing a new concept that's fine.
Here is a generic asscher and an Octavia photographed side by side.
Since the asscher on the left is almost double the carat weight of the Octavia so you could argue this pic is worthless for comparing spread, but it is useful for discussing perception of spread.
It shows the look of both, side by side.
The asscher has long bars and a big table.
You could argue this gives it a more spready look or feeling.

Ugh bad wording choice

.

Change 'perception of spread' to perception of faceup size.

We often correlate spread to faceup size, in modern rounds the differences in crown heights and table widths is a small percentage so this is reasonable. However in the case of Asscher's the crown heights and table widths have a more significant difference.

Also I have seen that despite the greater depth % differences, the spread between Octavia and Classical Asscher Cuts for the same carat weight is closer than would appear from the difference in depth % alone.
However the end visual result which is the perceived faceup size may still reflect the greater depth of the Octavia and that is what I meant.

 

[Rockdiamond]

Date: 3/26/2010 6:11:58 AM
Author: Paul-Antwerp

Date: 3/25/2010 2:34:50 PM

Author: Rockdiamond

BRAVO Paul!!!!


Your points are well thought out, and totally relevant.

I could not agree more.


To address a few points that have already come up:


Cinna- I agree with Karl, you did get lucky- but I''m sure your stone is a knockout!

You mentioned using a highly regarded appraiser.

To me, that is closely related to the points raised about ASET.

Here''s how: If the appraiser LOVES the diamond, that is ZERO guarantee the consumer will.


The main problem these type of tests is that they may produce false positives, or false negatives.

I''ve heard that term so many times- ''use this or that tool for rejection''


False negatives can be just as damaging as false positives as they can prevent the proper stone from being considered.


The ACA charts have this same problem- as well as another, which also bothers me greatly.

The ACA charts place ratings on stones.

A 1a is ''better'' than a 2a- right?

Well, if you''re the consumer who just bought a stone you LOVE, then plug in the numbers to find you bought a ''less than optimal'' stone, it can hurt. It might actually place a seed of doubt in the consumer''s mind with no basis whatsoever in fact. But a grading system like 1a, 2a etc sounds ''factual''

Again, false negatives can be just as bad as false positives.


Another aspect to this which is so very difficult is the lack of trust placed in diamond sellers.

There may be very good cause for this disdain, if we use ''averages''- but this is another area where false negatives can hurt the consumer.


I have enough PS scars no know NOT to refer to ASET as a ''gimmick''- but there are many sellers who have great ability to select and provide fancy shaped diamonds that might use the word.


But Kenny''s attitude ( feeling some sort of definitive test for fancy shapes is desperately needed) points out another common attitude here on PS.

There''s a mistrust of sellers- as well as a feeling that ''prosumers'' are effective at assisting consumers selecting fancy shapes.

Put this together and sometimes it can get antagonistic....which is a shame, especially considering how well PS is monitored- resulting in an atmosphere where I believe the regular posters ( both tradespeople and prosumers) are ALL genuinely interested in helping consumers.

David,


I took my time to read and re-read what you said. A lot of it is off-topic, I must say.


As long as we are discussing rounds, which is not the topic here, you are still not accepting that the rejection-tools used (lab''s cut-grade, HCA, ideal-scope, ASET) are indeed valid rejection-tools for brightness. In that way, the number of ''false negatives'' is extremely limited, when using these tools correctly.


Your defense of these ''false negatives'' is the same as coming up for the ''human'' rights of that poor neglected diamond. While very noble, this defense is not to the benefit of the consumer in any way.


As far as the real topic of this thread goes, you are coming up with arguments that are off-topic and that I definitely did not raise. You may have your beef with the AGA-charts (I do too), and you may even express that you are not using ASET because you find it too complicated and you do not understand it (the latter is clear), but it has no relation to my original post, which depicted the situation of a consumer, trying to make a first selection from a huge virtual list of fancy shapes. They do not have the data to use the AGA-charts, nor do they have ASET''s, not even a cut-grade of a lab. You might agree with me that the task for this consumer is close to impossible, but could you please limit your comment then to agreeing with it, and refrain from a post that turns my observation into a complete criticism of PS.


Live long,

Paul- In terms of me accepting validity of rejection tools "for brightness" ( your words), what if brightness is not as important as other aspects to some shoppers?

IN terms of protecting the "rights of a poor abused diamond" that is not my motivation- it is protecting the rights of CONSUMERS.

If a discussion involves an exchange of ideas, that is going to involves each participant relating their perception of statements made by other participants.

I don''t see how an exchange of ideas can occur unless we....well, exchange ideas.
I am not twisting your words, or your ideas- I have my own.
I was a little stunned that you somehow twisted my words into a "complete criticism of PS" as I feel my post was complimentary to the PS community. Indeed, the mere presence of this conversation- and many where I have raised alternative viewpoints , shows without a doubt that PS encourages diversity.


From my perspective every point I raise in your quote of my post is directly related to how consumers choose fancy shapes from a large list- such as the one on PS.

 

[Rockdiamond]

Let me answer the question directly
How can a consumer select a Fancy Shape from a huge virtual list?

Only by carefully selecting their vendor.
It''s really a simple matter.
If the consumer wants ASET images, that narrows it down a lot.

On sites that post photos, and or videos, that aspect is a great help- far more than measurements or any chart ( or ASET IMO).

Many vendors have an identifiable type of look in the stones they select. By using the photos, videos, ASET- but most importantly, interacting with a responsive vendor- they have the best shot at satisfaction.

Regardless of whatever we say here- the largest internet seller outsells everyone. And does so with no photos videos or ASET. IN that regard, overall, the point is moot. But not for those reading this.

 

[princesss]

Being a relative newbie to actually looking hard at fancies, I am really enjoying this thread. Sadly I''ve got nothing worthwhile to add, because I think my strategey has already been touched on - find the best vendor I can, do my research, and (if there''s a mismatch) figure out what I trust more - the vendor''s eyes or the numbers. Oh - and make sure that whoever I use has a good return policy.

I think with all of these tools, it comes down to trust. Do we trust the numbers, the pictures, the ASET, our eyes, the vendor...? With fancies, I don''t think we can necessarily trust any ONE thing to select the stone.

But that''s all I''ve got figured out.

 

[Garry H (Cut Nut)]

Date: 3/26/2010 6:17:55 AM
Author: Paul-Antwerp

Date: 3/25/2010 3:29:14 PM
Author: QueenMum
A part of the solution could be that every diamond is scanned.
Paul and Jonathan already do that, and I applaud them both for that.
But one problem remains, it is the .gem viewer.
Gem Advisor looks way too unreal.
DiamCalc looks much more realistic, but it isn''t for free.
It would be nice to have a limited DiamCalc version, just to view scanned diamonds without the possibility to modify the proportions.
I''m sure potential buyers are ready to pay a premium for diamonds visible in DiamCalc, and this premium could help dealers to finance the project with Octonus.

Considering that the majority of fancy shapes offered for sale are virtual, getting a scan of every stone is not feasible. And it still does not solve the challenge of the consumer looking at the huge virtual list without a clue where to start.

Live long,

Hi Queen Mum and Paul (and thanks for the timely topic Paul),

DiamCalc files can be viewed in High Dynamic Range (HDR) lighting - so yes - DaimCalc gives a better ''natural'' view than Gem Adviser, but HDR will come in GA.

Gem Adviser (GA) also gives some powerful free tools. Gem Adviser will be further developed to show inclusions (as per naked eye, loupe and microscope) and a diamonds true color based on a spectrum taken from the rough - I have just seen many of these planned enhancements last week.

Not all manufacturers will have this availability, but what we know is the leading 20 or so companies that have embraced OctoNus technology are also the fastest growing companies and they produce the type of diamonds that will make Pricescope fancy shape buyers very very happy. Sadly for some PS junkies, there will also be face up GA versions where cutters intellectual property will be protected from copying (at least until competitors buy a stone). Karl will be happy about that I am sure for Octavia.

1. ASET and Ideal-scope
2. Light return etc
for those that do not know - Gem Adviser is free ‘read-only’ DiamCalc software that also evaluates a diamond’s Light Return for mono and stereo views (i.e. 2 eyes see more flashes in a diamond than the results for a single eye).
Two other quantitative factors are also offered; Fisheye and DarkZone; which predicts the effect and size of annoying areas with little or no light return.
All OctoNus DiamCalc data compares the optical performance of any cut of diamond numerically to a bench-mark of 1.00 for a perfectly modeled Tolkowsky proportion round diamond.

These calculations are performed ‘on the fly’ on your computer and cannot be manipulated by suppliers!
You can also make movies of any diamond rocking back and forward

Many people may not know is you can open lots and lots of GA windows and compare all at once.

In short it is a part of the OctoNus Next Diamond plan to move a very large portion of the commoditized round diamond business into unique new fancy shapes by giving buyers safe tools to select (rather than just rejection tools). This will improve the saleability and liquidity of fancy shapes. The project also involves equiping manufacturers with advanced polishing tools to move to ensure replication of fancy shape stones that have exceptional appearance.

Currently very few companies can even replicate the same fancy twice. For example, you find a beauty and ask for another identical to be polished - it might take 5 to 10 try''s to get close.

Some of the GA options available are shown in the image below:

 

[Stephan]

Thank you for this great information, Garry!

 

[Paul-Antwerp]

Thank you for the update, Garry, but in my country, people are currently protesting against announcement-politics.

In short, politicians have been announcing new initiatives for many years, and in the end, almost none materialized.

Please be careful to avoid that trap. Looking back in the past 7 to 8 years, you already have a lot of announcements and predictions on your account.

Live long,

 

[diagem]

Date: 3/26/2010 7:16:16 AM
Author: Paul-Antwerp
Going back to the original topic, I see a lot of agreement with the fact that a consumer is facing an impossible task to select a few candidates from the virtual list.

At best, we must acknowledge that these initial choices are possibly coming to the forum, in order to get further advice from our regulars. So, if not on potential cut-quality, what is this initial selection based upon? Considering the options, I think that it will be entirely based upon carat weight, colour and clarity, AND most importantly price, compared to the other three factors. Basically, chances are great that a consumer starting his search on the virtual list will first consider the ones priced apparently cheapest, considering weight, colour and clarity.

I might be wrong, but I think that the probability of getting a great cut-quality when the first rejection is based upon price is relatively small.

As such, if our regulars take this first selection for granted, and try to choose the best in that selection, I fear that we are not doing the consumer a favour. Maybe, we should reflect upon reply-strategies.

Looking forward to your thoughts on that.

Live long,

I tend to agree with your concern..., but I also am concerned with the opposite as well

.

Let me start by saying PS is a great asset for any consumer who is looking for a Diamond feasible to justify the investment.
The information rooted in these threads is invaluable & with patience a consumer can significantly improve his/her chances of getting a great rock.
Virtual lists are basically "the" jungle of Diamonds offered on the open market (B2B or B2C) and tools are required to be able to sort through them.
IMO, the most productive tool is a trusted professional vendor with a good track-record for picking & matching beautiful Diamonds to consumer’s requests. And if a consumer is willing to spend the time they will find numerous options on PS that fit that bill (after all..., this is one of many positive features PriceScope offers

).
Other tools are bi-products that let these ''trusted vendors & appraisers'' relay/translate the information to consumers (especialy online).
Prosumers are IMO the bridge that connects the info passing from the trusted vendors to the consumers & are too a great asset as not all vendors have the time or patience to educate each and every potential client (some exceptions exist

).
So saying "I fear that we are not doing the consumer a favour" is an incorrect statement IMO.
I dont totally agree with the charts either..., but I do believe they are needed and act as one of the bi-products that definitely limit potential unwanted options.
Since AGA was mentioned here in your initial post..., I will say its a reliable chart executed by a longstanding professional member of PS with a proven track-record! I believe David should amend the chart as Diamond cut innovation advances but that is up to him if he wishes to keep his charts updated. What is important is it does help consumer stay within the mainstream of decent proportions.

Now to my concern which actually is a reflection of yours.
Educated PS vendors & prosumers will do their honest best attempts to limit the scope of options to match a preferable Diamond which can fit the consumers request.
I have seen potential beautiful Diamonds overlooked (or rejected) because the tools & numbers & information were not on the level of ‘great cut quality’ expected here on PS but IMO still had good potential.
There is no doubt in my mind human intervention is a must when looking for a beautiful fancy cut Diamond (virtually or not).
Tools developed to show appearances based on light performance exist and help both professionals & consumers, but IMO light performance is just a piece of the beauty pie

.
It would be nice to witness the evolution of tools become available in the future to ease on the wide matching process, but until then I am afraid professional educated vendors will be needed and what better place to find one but here on PriceScope.

I strongly believe the greater majority of consumers that purchased their Diamonds after educating themselves on PS got a great rock!

 

[oldminer]

Diagem and all;

I''d love to amend the AGA system for the better, but I have found few who would be both unbiased AND qualified to accomplish the task. There are many independent appraisers who do valuation work, who are unbiased and experienced, but do not have the trade experience to make valid changes to the system. There are cutters, retailers and dealers who know lots about diamonds and I have taken some advice generously offered by them with restraint because one must guard against favoring a particular cut style or an agenda in branding. I wish I had sufficent scientific knowledge to do more to imporve the system on my own, but I think I have done what I am capable of doing already.

My fear is that wrangling over the details required for each shape would prove unproductive or provoke arguments for which we''d find no solution. The sytem will never be perfect as there are too many cut variables to simplify into a few parameters. No matter how "improved" there will be naysayers who insist that it is not 100% correct and therefore worthless. They may be wrong, but their vocal complaints don''t seem to be much mitigated by calm reasoning. This confuses consumers and the whole point of the system was to help people who who will never know the subject well enough to go it alone.

The most logical approach would be to make small adjustments to existing parameters, merge the 1A and 1B into a single broader category, and possibly add a couple more parameters which science can substantiate as valid. We have no mechanism to come together on such a task and no way to control biased input which might serve to weaken the process or the end result. I am not committed to the status quo and never have been. I''d be glad to see the system made more meaningful, remain unbiased and more properly screen diamonds for craftsmanship quality.

The support I get is important to me and the criticism is heard, too. No one should oversell what the system can do. Although it was not the work of the GIA or AGS, I believe there is validity to screening in this way, especially for distant selection or for consumers who simply do not understand the inherent visual size and durability issues with diamonds.

 

[Karl_K]

Dave,

I have a lot of respect for you and the work you put in the system.
For its time it was great but like many things technology and the gains in knowledge have left it behind in my opinion.
There are simply better ways of doing things today.

 

[Rockdiamond]

David- I''d like to wholeheartedly agree with Karl.
I have a LOT of respect for you- and the work you''ve done.
Without a doubt, when passionate people discuss issues that include differences of opinion, it can get heated.
However that should not be taken as a challenge to anyone''s intentions, or capability.
In many ways, drawing the charts was an impossible task- given the lack of consensus among experts in the field when you drew them- and even more today.


This thread is very encouraging to me, as one who has taken some heat for differences of opinions with other respected professionals.
This thread proves beyond the shadow of a doubt that old saying: There''s more than one way to skin a cat

 

[ChunkyCushionLover]

Until the day comes when all cutters (who care about light performance) run a helium scan on their finished product and this is converted to .gem files for customer viewing in various lighting. We will still be using numercial charts and reflector technologies as the only tools we have.

This applies to tradesmembers, vendors, retailers, wholesalers and lowly consumers.

I see value in the AGA charts and notwithstanding their limitations will continue to reference them for shapes I haven''t studied closely.

 

[Stephan]

AGS observation distance: 25 cm
HCA observation distance: 40 cm

That is the problem.
THE grading system only will consider stones that flash from a 3-4m distance.
Am I wrong again?

 

[Paul-Antwerp]

Looking at the various reactions, I see the advice of choosing a good trusted vendor, with a proven record in fancy shapes, as the generally accepted one.

Considering this, in my experience, it is safe to assume that such good vendors also have supply-relationships with cutters, who are not offering their production on any virtual list. I think that we could say that such vendors are fishing in a much bigger pond, with the ability of making a much better goal-oriented pre-selection because of their relationship/communication with specific cutters.

Does this sound correct?

If so, should the general PS-advice, currently aimed at stone-assessment of a pre-selection by the consumer, not go more towards finding the best vendor for the consumer''s desires?

Live long,

 

[Serg]

re:Looking at the various reactions, I see the advice of choosing a good trusted vendor, with a proven record in fancy shapes, as the generally accepted one.


is "50 years" old fashion diamond business model + advertisement in Internet ( to increase Trust) good enough for modern Internet consumer ?

Are consumers prefer compare Trust-Brand instead diamonds-Beauty?

 

[diagem]

Date: 3/29/2010 6:42:51 AM
Author: Serg
re:Looking at the various reactions, I see the advice of choosing a good trusted vendor, with a proven record in fancy shapes, as the generally accepted one.


is ''50 years'' old fashion diamond business model + advertisement in Internet ( to increase Trust) good enough for modern Internet consumer ?

Are consumers prefer compare Trust-Brand instead diamonds-Beauty?

Trust-Brand limits beauty.

 

[Paul-Antwerp]

Date: 3/29/2010 6:42:51 AM
Author: Serg
re:Looking at the various reactions, I see the advice of choosing a good trusted vendor, with a proven record in fancy shapes, as the generally accepted one.


is ''50 years'' old fashion diamond business model + advertisement in Internet ( to increase Trust) good enough for modern Internet consumer ?

Are consumers prefer compare Trust-Brand instead diamonds-Beauty?

Good question, Sergey.

15 years of Internet has apparently evolved in offering consumers the false security of having them choose our of a huge selection of virtual stones, without the consumer having any real tool to distill a shortlist of the best possible candidates.

Considering that, a better solution might well be to have the consumer buy a rough stone, and have him arrange the actual cutting in co-operation with the cutter. As it stands, this business-model does not exist yet and we still need to see whether the ''trust-the-machine, trust-the-cutter, trust-the-system''-model will be a success.

For now, working with your vendor as your ally in finding the best fancy shape for you seems to be the best approach. I can think of certain initiatives that could be organised on the Internet, to make the process even more trustworthy.

Live long,

 

[diagem]

Date: 3/29/2010 1:23:30 PM
Author: Paul-Antwerp

Date: 3/29/2010 6:42:51 AM
Author: Serg
re:Looking at the various reactions, I see the advice of choosing a good trusted vendor, with a proven record in fancy shapes, as the generally accepted one.


is ''50 years'' old fashion diamond business model + advertisement in Internet ( to increase Trust) good enough for modern Internet consumer ?

Are consumers prefer compare Trust-Brand instead diamonds-Beauty?

Good question, Sergey.

15 years of Internet has apparently evolved in offering consumers the false security of having them choose our of a huge selection of virtual stones, without the consumer having any real tool to distill a shortlist of the best possible candidates.

Considering that, a better solution might well be to have the consumer buy a rough stone, and have him arrange the actual cutting in co-operation with the cutter. As it stands, this business-model does not exist yet and we still need to see whether the ''trust-the-machine, trust-the-cutter, trust-the-system''-model will be a success.

For now, working with your vendor as your ally in finding the best fancy shape for you seems to be the best approach. I can think of certain initiatives that could be organised on the Internet, to make the process even more trustworthy.

Live long,

We are always open to learning new approaches...

 

[Garry H (Cut Nut)]

Date: 3/29/2010 4:51:17 PM
Author: DiaGem

Date: 3/29/2010 1:23:30 PM
Author: Paul-Antwerp

Date: 3/29/2010 6:42:51 AM
Author: Serg
re:Looking at the various reactions, I see the advice of choosing a good trusted vendor, with a proven record in fancy shapes, as the generally accepted one.


is ''50 years'' old fashion diamond business model + advertisement in Internet ( to increase Trust) good enough for modern Internet consumer ?

Are consumers prefer compare Trust-Brand instead diamonds-Beauty?

Good question, Sergey.

15 years of Internet has apparently evolved in offering consumers the false security of having them choose our of a huge selection of virtual stones, without the consumer having any real tool to distill a shortlist of the best possible candidates.

Considering that, a better solution might well be to have the consumer buy a rough stone, and have him arrange the actual cutting in co-operation with the cutter. As it stands, this business-model does not exist yet and we still need to see whether the ''trust-the-machine, trust-the-cutter, trust-the-system''-model will be a success.

For now, working with your vendor as your ally in finding the best fancy shape for you seems to be the best approach. I can think of certain initiatives that could be organised on the Internet, to make the process even more trustworthy.

Live long,

We are always open to learning new approaches...

Hmmm, so we rate the vendor?
We forget about the product reiviews and assesments from independant 3rd parties (car reviews, wine writters, stock brokers etc) and we go to vendors just like how we pick which department store to shop in?
How do I know vendor X likes the same cushion as me?
How does vendor x know or discover my taste?

 

[ChunkyCushionLover]

Date: 3/29/2010 5:45:00 AM
Author: Paul-Antwerp
Looking at the various reactions, I see the advice of choosing a good trusted vendor, with a proven record in fancy shapes, as the generally accepted one.

They are still a vendor trying to make a sale, that is not enough, their comments and actions work towards making a sale not always towards finding the ideal stone for the consumer.

In my opinion:

No Video + No Reflector Tests = No Trust

Considering this, in my experience, it is safe to assume that such good vendors also have supply-relationships with cutters, who are not offering their production on any virtual list. I think that we could say that such vendors are fishing in a much bigger pond, with the ability of making a much better goal-oriented pre-selection because of their relationship/communication with specific cutters.

They do but the same cutting house doesn''t always consistantly provide the same cut quality.


Does this sound correct?

If so, should the general PS-advice, currently aimed at stone-assessment of a pre-selection by the consumer, not go more towards finding the best vendor for the consumer''s desires?

In my mind it starts with an evaluation of how strict the consumer''s priority is on cut for light performance. If the perception is that consumer wants the best light performance for a given outline then it usually ends with the reccomendation of only a select few vendors that provide the reflector tools and/or video. Vendors who don''t provide the visual proof of the cut quality of their fancy shapes really cannot be easily reccomended, even if they have excellent stones they can''t prove it no matter how much they describe the virtues of their stock.

In the end the consumer may be presented with choices and will decide the important tradeoff between lower price and the most strict selection based on cut. Particular selection based on narrow ranges of color, LW ratio, shape outline, facet design, clarity, and carat weight may even further limit the choices available.

I think it is important that in forums we inform novice consumers of the differences between excellent, average and mediocre fancy cut stones based on their light performance criteria and not send them to the "trusted" vendor blind and with their guard down because a particular vendor as a reputation for sourcing a particular quality of stone.

In order to do this I have to choose vendors who provide reliable data to judge this.


Live long,

 

[Paul-Antwerp]

Date: 3/29/2010 8:16:13 PM
Author: Garry H (Cut Nut)

Date: 3/29/2010 4:51:17 PM
Author: DiaGem

Date: 3/29/2010 1:23:30 PM
Author: Paul-Antwerp

Date: 3/29/2010 6:42:51 AM
Author: Serg
re:Looking at the various reactions, I see the advice of choosing a good trusted vendor, with a proven record in fancy shapes, as the generally accepted one.


is ''50 years'' old fashion diamond business model + advertisement in Internet ( to increase Trust) good enough for modern Internet consumer ?

Are consumers prefer compare Trust-Brand instead diamonds-Beauty?

Good question, Sergey.

15 years of Internet has apparently evolved in offering consumers the false security of having them choose our of a huge selection of virtual stones, without the consumer having any real tool to distill a shortlist of the best possible candidates.

Considering that, a better solution might well be to have the consumer buy a rough stone, and have him arrange the actual cutting in co-operation with the cutter. As it stands, this business-model does not exist yet and we still need to see whether the ''trust-the-machine, trust-the-cutter, trust-the-system''-model will be a success.

For now, working with your vendor as your ally in finding the best fancy shape for you seems to be the best approach. I can think of certain initiatives that could be organised on the Internet, to make the process even more trustworthy.

Live long,

We are always open to learning new approaches...

Hmmm, so we rate the vendor?
We forget about the product reiviews and assesments from independant 3rd parties (car reviews, wine writters, stock brokers etc) and we go to vendors just like how we pick which department store to shop in?
How do I know vendor X likes the same cushion as me?
How does vendor x know or discover my taste?

Rating the vendor is not what I had in mind. But let me first check in the next weeks, to see whether my idea can be set up, before I explain any further in public.

Live long,

 

[Paul-Antwerp]

Date: 3/30/2010 1:39:04 AM
Author: ChunkyCushionLover

Date: 3/29/2010 5:45:00 AM
Author: Paul-Antwerp
Looking at the various reactions, I see the advice of choosing a good trusted vendor, with a proven record in fancy shapes, as the generally accepted one.

They are still a vendor trying to make a sale, that is not enough, their comments and actions work towards making a sale not always towards finding the ideal stone for the consumer.

In my opinion:

No Video + No Reflector Tests = No Trust

Considering this, in my experience, it is safe to assume that such good vendors also have supply-relationships with cutters, who are not offering their production on any virtual list. I think that we could say that such vendors are fishing in a much bigger pond, with the ability of making a much better goal-oriented pre-selection because of their relationship/communication with specific cutters.

They do but the same cutting house doesn''t always consistantly provide the same cut quality.


Does this sound correct?

If so, should the general PS-advice, currently aimed at stone-assessment of a pre-selection by the consumer, not go more towards finding the best vendor for the consumer''s desires?

In my mind it starts with an evaluation of how strict the consumer''s priority is on cut for light performance. If the perception is that consumer wants the best light performance for a given outline then it usually ends with the reccomendation of only a select few vendors that provide the reflector tools and/or video. Vendors who don''t provide the visual proof of the cut quality of their fancy shapes really cannot be easily reccomended, even if they have excellent stones they can''t prove it no matter how much they describe the virtues of their stock.

In the end the consumer may be presented with choices and will decide the important tradeoff between lower price and the most strict selection based on cut. Particular selection based on narrow ranges of color, LW ratio, shape outline, facet design, clarity, and carat weight may even further limit the choices available.

I think it is important that in forums we inform novice consumers of the differences between excellent, average and mediocre fancy cut stones based on their light performance criteria and not send them to the ''trusted'' vendor blind and with their guard down because a particular vendor as a reputation for sourcing a particular quality of stone.

In order to do this I have to choose vendors who provide reliable data to judge this.


Live long,

I fully agree, CCL.

But take the following situation: A new poster (consumer) starts a thread on PS, asking which of three pear-shapes he should choose. Cut-quality is important to him, and he has done his homework and has ASET-pics on all three. His selection of three however comes from the virtual list and is based upon criteria, that according my original post, are dubious and unlikely to lead to the cut-quality that he desires.

I see the regular poster''s position as very problematic, like in a real dilemma.

Either, one says which of the three is the best, well knowing that the pre-selection was at random and that the consumer could get a lot better with proper assistance.

Or, should one take the process back one level, explaining that the initial pre-selection might not be the best. This raises other problems, since a regular poster will have the same difficulty in finding a better alternative: the virtual list does not give sufficient information.

Live long,