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GIA India - is this junk?

WinkHPD

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Texas Leaguer|1414185089|3772216 said:
Wink|1414183677|3772205 said:
MelisendeDiamonds|1414122597|3771946 said:
<Snip>

Those vendors consistently recommended here are also the same vendors who tend to disparage GIA XXX

<Snip>

I am one of those vendors who disparage GIA XXX and will continue to do so since it is a basically worthless grade that encompasses both beautiful and lifeless diamonds under the auspice of XXX.

When they publish a cut grade based on science I will be ecstatic in my change of tune.

Wink
Though I respect Wink's opinion, I am NOT one of those vendors who disparage GIA XXX. No more than I disparage a GIA Si1. There are some Si1 that are great, some that are so-so, and some that I would not buy.

I respect GIA for coming out with a cut grade for rounds, even if it is not as rigorous as it could be. When they finally did, cutting got better industry-wide. I look forward to the day when they do the same for princess cuts for the same reason.

For someone looking for the best of the best in terms of cut quality, you certainly cannot simply look for a GIA XXX and call it a day. You have to do more evaluation. But I also don't think I have ever seen a GIA XXX that was "lifeless" due to cut quality.

Let me give a better response. You are correct "lifeless" is too strong a word, but the real problem is that GIA has a double standard. Excruciatingly incremental descending color grades DEF etc. Invisible differences in the top 6-7 clarity grades and yet a single grade of EX for cut which unarguably permits visibly different levels of light return... And CUT has more impact on life than color or clarity. So why the double standard?

In my opinion it is because it allows the cutters to make more money selling diamonds at 1.00 or slightly larger that should have finished well below that 1ct mark if they were cut for beauty. When a cutter is able to milk a few percent more per each diamond by cutting steep deeps, then what a not surprising turn that it is now the steep deep that we see most often when looking through lots of GIA XXX for a decent looking diamond. If you cutting hundreds, or thousands of stones per month, this is BIG money. The GIA XXX allows the vendors to make more money and GIA profits from selling more reports to happy vendors while the public by and large gets a less appetizing (visually) product.

Just seems wrong to me, so disparaging I will go...

When they deign to do it right, I will sing a new tune, and gladly.

Wink
 

WinkHPD

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Texas Leaguer|1414185089|3772216 said:
Wink|1414183677|3772205 said:
MelisendeDiamonds|1414122597|3771946 said:
<Snip>

Those vendors consistently recommended here are also the same vendors who tend to disparage GIA XXX

<Snip>

I am one of those vendors who disparage GIA XXX and will continue to do so since it is a basically worthless grade that encompasses both beautiful and lifeless diamonds under the auspice of XXX.

When they publish a cut grade based on science I will be ecstatic in my change of tune.

Wink
Though I respect Wink's opinion, I am NOT one of those vendors who disparage GIA XXX. No more than I disparage a GIA Si1. There are some Si1 that are great, some that are so-so, and some that I would not buy.

I respect GIA for coming out with a cut grade for rounds, even if it is not as rigorous as it could be. When they finally did, cutting got better industry-wide. I look forward to the day when they do the same for princess cuts for the same reason.

For someone looking for the best of the best in terms of cut quality, you certainly cannot simply look for a GIA XXX and call it a day. You have to do more evaluation. But I also don't think I have ever seen a GIA XXX that was "lifeless" due to cut quality.

Let me give a better response. You are correct "lifeless" is too strong a word, but the real problem is that GIA has a double standard. Excruciatingly incremental descending color grades DEF etc. Invisible differences in the top 6-7 clarity grades and yet a single grade of EX for cut which unarguably permits visibly different levels of light return... And CUT has more impact on life than color or clarity. So why the double standard?

In my opinion it is because it allows the cutters to make more money selling diamonds at 1.00 or slightly larger that should have finished well below that 1ct mark if they were cut for beauty. When a cutter is able to milk a few percent more per each diamond by cutting steep deeps, then what a not surprising turn that it is now the steep deep that we see most often when looking through lots of GIA XXX for a decent looking diamond. If you cutting hundreds, or thousands of stones per month, this is BIG money. The GIA XXX allows the vendors to make more money and GIA profits from selling more reports to happy vendors while the public by and large gets a less appetizing (visually) product.

Just seems wrong to me, so disparaging I will go...

When they deign to do it right, I will sing a new tune, and gladly.

Wink
 

Texas Leaguer

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Wink|1414185933|3772220 said:
Texas Leaguer|1414185089|3772216 said:
Wink|1414183677|3772205 said:
MelisendeDiamonds|1414122597|3771946 said:
<Snip>

Those vendors consistently recommended here are also the same vendors who tend to disparage GIA XXX

<Snip>

I am one of those vendors who disparage GIA XXX and will continue to do so since it is a basically worthless grade that encompasses both beautiful and lifeless diamonds under the auspice of XXX.

When they publish a cut grade based on science I will be ecstatic in my change of tune.

Wink
Though I respect Wink's opinion, I am NOT one of those vendors who disparage GIA XXX. No more than I disparage a GIA Si1. There are some Si1 that are great, some that are so-so, and some that I would not buy.

I respect GIA for coming out with a cut grade for rounds, even if it is not as rigorous as it could be. When they finally did, cutting got better industry-wide. I look forward to the day when they do the same for princess cuts for the same reason.

For someone looking for the best of the best in terms of cut quality, you certainly cannot simply look for a GIA XXX and call it a day. You have to do more evaluation. But I also don't think I have ever seen a GIA XXX that was "lifeless" due to cut quality.

Let me give a better response. You are correct "lifeless" is too strong a word, but the real problem is that GIA has a double standard. Excruciatingly incremental descending color grades DEF etc. Invisible differences in the top 6-7 clarity grades and yet a single grade of EX for cut which unarguably permits visibly different levels of light return... And CUT has more impact on life than color or clarity. So why the double standard?

In my opinion it is because it allows the cutters to make more money selling diamonds at 1.00 or slightly larger that should have finished well below that 1ct mark if they were cut for beauty. When a cutter is able to milk a few percent more per each diamond by cutting steep deeps, then what a not surprising turn that it is now the steep deep that we see most often when looking through lots of GIA XXX for a decent looking diamond. If you cutting hundreds, or thousands of stones per month, this is BIG money. The GIA XXX allows the vendors to make more money and GIA profits from selling more reports to happy vendors while the public by and large gets a less appetizing (visually) product.

Just seems wrong to me, so disparaging I will go...

When they deign to do it right, I will sing a new tune, and gladly.

Wink
I cannot disagree with the specifics you site Wink. I guess I am just more understanding about the pressures GIA faced from a world-wide constituency when developing their cut grade system. Yes, cutters are now cutting to the outer boundaries of the EX range, and those stones are not what we would necessarily call excellent. However, think about all the stones in the market that were not even very good and were being touted as top cuts. GIA had to make ALOT of their clients very unhappy. So, it is understandable that they made it as forgiving as possible while still fulfilling their mission to improve consumer protection. Remember that it was almost 10 years after AGS proved that consumers were keenly interested in cut quality that GIA finally came out with a system. You could almost feel them biting their nails and dragging their feet!

In a sense, the position GIA took left room in the market for the growth of AGS to serve that portion of the consumer market interested in more scientifically rigorous, light performance based cut grading. And that is a good thing in my opinion.
 

Rockdiamond

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Wink- I Luv ya man- but we definitely disagree about GIA cut grade being "worthless"
You're painting a picture in black and white- but there's plenty of shades of grey.
If we are looking at two potential stones from the same rough- say a 1.00ct GIAXXX cut to make the 1ct mark, scoring above 3 on HCA versus a .93ct Super ideal AGS000 HCA<2
I do happen to agree that I've seen a few- very few- GIA XXX stones that I would not have called well cut. But the vast majority are indeed well cut.
Yes, there's a difference in super ideal stones and regular old really well cut diamonds. But that does not mean that some people won't justifiably pick the 1.00ct.
It might be that they want a 1.00ct and that's their budget- or they may actually prefer how the non super ideal performs. It's a fact that not everyone will pick a super ideal versus a "regular" GIA XXX when viewed in person.

My point is that if a cutter can save a few points, and still come out with a great looking diamond, yet forego super ideal, it's certainly a viable choice. It doesn't make them some evil greedy diamond cutting company.
There's demand for both.
Even from the financial standpoint, badly cut stones look bad to most people, are harder to sell, and go for lower prices.

Plus, you're also not mentioning the fact that cutting to super ideal standards is simply not possible on a large scale- it requires the top cutters in terms of skill and a lot more time per stone.
There's a reason the best of the best cut costs more- and such stones will always be more rare.
But not everyone wants or needs to buy the best of the best.

GIA EX cut grade has done a lot to assist millions of consumers. It's also brought the quality of the "average" stones up tremendously. Shooting for GIA XXX may not be as good in your eyes as shooting for AGS0 cut grade- but its certainly better than shooting at nothing.

Personally I think GIA's cut grade is as helpful that AGS000 grade- if only because it allows a wider variety of light performance and helps a lot more consumers.
 

Rockdiamond

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A question for you guys about "scientific"
Is polling people on how diamonds look "scientific"?

ETA- I think we all agree about far more than we disagree about.
I do feel that using the term "scientific" needs to be used in equal share for GIA and AGSL grading.
It's not that GIA does not have adhere to sciencentific methodogy. GIA has far more in the way of resources to expand the scientific evaluation of diamonds. And they're putting them to use in that regard.
 

Texas Leaguer

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Rockdiamond|1414188384|3772249 said:
A question for you guys about "scientific"
Is polling people on how diamonds look "scientific"?
Yes, polls can be scientific. Most of the social sciences only have polls, surveys and statistics to use as their inputs. Whether the science is good depends upon things like the design of the study, how rigorously it is controlled, and whether the sample size is sufficient to draw meaningful conclusions.
 

Karl_K

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Texas Leaguer|1414189896|3772258 said:
Rockdiamond|1414188384|3772249 said:
A question for you guys about "scientific"
Is polling people on how diamonds look "scientific"?
Yes, polls can be scientific. Most of the social sciences only have polls, surveys and statistics to use as their inputs. Whether the science is good depends upon things like the design of the study, how rigorously it is controlled, and whether the sample size is sufficient to draw meaningful conclusions.
And if the right people are polled. In the case of GIA it was mostly trade members who where polled what does polling trade members tell you about what consumers would see in that diamond?
Not much because they look at diamonds in a totally different way and have an inherent bias.

That is like polling a region where people grew up eating spicy food to find out when a product is too spicy for the average person.
The inherent bias of being used to eating spicy food will make the results useless when applied to the larger population.
 

Texas Leaguer

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Karl_K|1414190336|3772263 said:
Texas Leaguer|1414189896|3772258 said:
Rockdiamond|1414188384|3772249 said:
A question for you guys about "scientific"
Is polling people on how diamonds look "scientific"?
Yes, polls can be scientific. Most of the social sciences only have polls, surveys and statistics to use as their inputs. Whether the science is good depends upon things like the design of the study, how rigorously it is controlled, and whether the sample size is sufficient to draw meaningful conclusions.
And if the right people are polled. In the case of GIA it was mostly trade members who where polled what does polling trade members tell you about what consumers would see in that diamond?
Not much because they look at diamonds in a totally different way and have an inherent bias.

That is like polling a region where people grew up eating spicy food to find out when a product is too spicy for the average person.
The inherent bias of being used to eating spicy food will make the results useless when applied to the larger population.
Yes, the design and control of any study is critical to the validity of the results. I do think GIA made an effort for the survey to be meaningful, but I am sure an independent audit by the scientific community would find deficiencies. Did they design their poll in a way intended to validate their grading construct? I think that is a legitimate question.
 

drk14

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MelisendeDiamonds|1414129920|3771988 said:
iv) Ship the diamond to my office and inspect it prior to shipping to the customer
v) Tell the supplier to ship directly to the customer

While for most customers especially B2B I only have to do v) that doesn't preclude me from doing i) to iv) on a case by case basis does that make me a "dropshipper"?

To answer your question, if you do not routinely do iv) for customers (excluding B2B sales, which are largely irrelevant to PS), yes, in my opinion you would be considered a drop-shipper as the term is used on PS. That being said, as you have already pointed out, "there is nothing disreputable on its face about a dropshipping vendor." It's just that most PSers seem to appreciate (and are willing to pay a little extra for) the value added services provided by those vendors who don't just drop-ship. And as TexasLeager has pointed out, there are various degrees to which the vendor can evaluate the diamond before finalizing the sale.

For purchase of virtual diamonds, PS tends to recommend those vendors who (1) are known to be reputable, (2) make it easy for consumers to select candidate diamonds that are likely to be winners, (3) provide in-house QC and additional evaluation/analysis prior to sale, (4) have risk-free return policies and generous upgrade policies. Drop-shippers who satisfy at least (1) and (4) are also sometimes recommended on PS, especially to consumers who have very tight budgets.



Disclaimer: Clearly, I don't speak for PS (or its members). The above are my impressions about what goes on here. :bigsmile:
 

MollyMalone

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Texas Leaguer|1414180847|3772190 said:
I think the reference [to "imported diamonds"] is to bringing in a virtual diamond that is located outside the US. There are logistics considerations and costs associated with the process that some companies don't want to take on. Especially if they are offering a return privilege, where returning it to the foreign supplier may not be an option.
That's what I was thinking, but didn't want to assume. So I appreciate your informative response to my query up-thread, thanks.
 

Rockdiamond

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Karl_K|1414190336|3772263 said:
Texas Leaguer|1414189896|3772258 said:
Rockdiamond|1414188384|3772249 said:
A question for you guys about "scientific"
Is polling people on how diamonds look "scientific"?
Yes, polls can be scientific. Most of the social sciences only have polls, surveys and statistics to use as their inputs. Whether the science is good depends upon things like the design of the study, how rigorously it is controlled, and whether the sample size is sufficient to draw meaningful conclusions.
And if the right people are polled. In the case of GIA it was mostly trade members who where polled what does polling trade members tell you about what consumers would see in that diamond?
Not much because they look at diamonds in a totally different way and have an inherent bias.

That is like polling a region where people grew up eating spicy food to find out when a product is too spicy for the average person.
The inherent bias of being used to eating spicy food will make the results useless when applied to the larger population.

I can see why you might feel that way Karl- but also consider the other side.
There's a lot of very knowledgeable dealers out there- and there's also quite a diversity of taste- even between dealers.
I totally respect dealers that create a super culled inventory of super ideal stones. I know why they cost more, and understand why they are worth more to selected consumers.
If a dealer like Wink was surveyed, I'm sure he'd lean towards super ideal. Having a discriminating eye, and strong taste is an important element for any successful dealer IMO. Kudos to Wink- he's passionate.

Personally I believe that the wider GIA grade is more reflective of a broader swath of visual tastes in the consumer market.
I base this on many thousands of discussions with real life consumers.
There's a lot of dealers that really have their finger on the pulse of what consumers want, as well as the diamond trade overall.
I agree that an effective poll would be largely based on consumer survey- but I also believe that surveying as many knowledgeable tradespeople as possible would be an important component.
 

Karl_K

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Rockdiamond|1414266945|3772571 said:
If a dealer like Wink was surveyed.
Polling 10000 Wink's would not be even less scientifically accurate than polling 10000 random trade members.
Consumers would be better off if there were 10000 Wink's in the trade. Not that he is perfect :}

Rockdiamond|1414266945|3772571 said:
Having a discriminating eye, and strong taste is an important element for any successful dealer IMO.
That is exactly my point trade members do not look at diamonds in a way that can be considered average for consumers.
Rockdiamond|1414266945|3772571 said:
I agree that an effective poll would be largely based on consumer survey- but I also believe that surveying as many knowledgeable tradespeople as possible would be an important component.
A separate poll with the same presentation and questions for trade members would be interesting.
 

denverappraiser

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The biggest problem with designing polls is in deciding what to measure. Popular is not a synonym for better any more than brilliance is a synonym for beauty. When asked about what they want in a diamond, nearly everyone says brilliance, sparkle, fire, and life or words to these effect. The problem is that not everyone agrees with what these things actually are. The GIA study asked people to force rank several stones chosen from a collection of about 60 different samples. They collected over 700,000 observations and carefully compiled the data based on which got a lot of votes, which got a few and so on. That’s definitely scientific, but what exactly is being measured here? Beauty? Brilliance? Sparkle? None of the above. It’s popularity. From the standpoint of dealers, that’s definitely an important attribute. They want things that sell, and popular things sell better than unpopular ones. That just makes sense. The trick is when you take the next step and tell a customer that one stone is better than another. Better in what way? It’s more popular? It’s likely to sell better? So what?

AGS took a different approach when they designed their scale. Their science was to mathematically decide what they thought was best in terms of light reflections and then work backwards from there. There’s a margin around the attributes of that optimum stone and things within that margin are called ‘ideal’. Things outside of it are not. This is not immune to criticism either. Not everyone agrees on their model of the perfect diamond, for the same reasons that not everyone voted for the same stone in the GIA study. Beauty is a judgment thing. AGS has a much narrower target, but if that target isn’t centered on what you like then it’s a serious problem.
 

Rockdiamond

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Great post Neil.
In essence what I read – and a problem that I found to exist for a long time, is that both are based on poll results, but GA's poll was 700,000+ people, and AGS Is interpreting the light return data based on a way smaller sampling of taste- basically their own internal poll.
I still feel that it's completely out of line to say one grade is based on science and the other one isn't.
 

denverappraiser

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What AGS did that makes theirs more like 'real' science, is present it to peer review and publish both the methodology and the results, in full. GIA takes the position that they have no peers. :saint:
 

Rockdiamond

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I agree that publishing methodology as well as results does offer greater transparency and is beneficial.
However the peer review is doing what Karl warned about.
The peer review was far too narrow. Although you do get a much more finite result, it Will not be representative of a broad swath of taste.
If we look at princess cut grading by AGSL, A lot of very knowledgeable people feel that it goes too far in one direction. A position with which I agree wholeheartedly.
 

MelisendeDiamonds

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denverappraiser said:
.... They collected over 700,000 observations

Rockdiamond|1414337352|3772912 said:
Great post Neil.
In essence what I read – and a problem that I found to exist for a long time, is that both are based on poll results, but GA's poll was 700,000+ people, and AGS Is interpreting the light return data based on a way smaller sampling of taste- basically their own internal poll.
I still feel that it's completely out of line to say one grade is based on science and the other one isn't.

denverappraiser|1414339973|3772928 said:
What AGS did that makes theirs more like 'real' science, is present it to peer review and publish both the methodology and the results, in full. GIA takes the position that they have no peers. :saint:

Usually if you want to debate something credibly and be taken seriously you should research your subject thoroughly, read carefully, and check your facts.

When was the last time either of you reviewed :read: the Gems and Gemology articles on the Foundations of GIA's cut grading system? (G&G Fall 2004 and references therein.)

GIA reported there were ~300 people who participated in the ~70,000 observations, 100 were from the GIA lab itself.
(This is of course assuming you trust the data accuracy and peer review of G&G but lets just say its reliably under these numbers but in the same order of magnitude.)
 

Rockdiamond

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It's great if anyone can add constructive information to a discussion. I don't remember reading the article from 2004, and it's 10 years old at this point. If you possess information from the article that would add to the discussion how about telling us?
I am not clear what you meant about 300 observers or 70,000 observers…
How many peers reviewed the AGS results?
 

denverappraiser

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300 observers. 70,000 observations. Individual viewers said multiple things. He's correct that I made a typo in the above post.

Submitting to peer review is a matter of publishing your data, methodology, and results in a public way so that others can reasonably evaluate what you've done. There's no good way to count how many actually read it and, by the way, peer review doesn't make you right, it's just part of the scientific process. It's something GIA hasn't done. The data was kept secret and the methodology and algorithms leading to their conclusions were (and are) secret. That's not peer review, it's advertising.
 

Rockdiamond

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Interesting Neil. Where was the data published? What was the mechanism for the people reviewing it to make criticisms, and/or comments?
I do not recall ever reading the AGS literatur asking for comment. Was it a general publication, or aimed specifically at AGS members?
 

cflutist

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I had saved this 48 page JCK publication from November 2004 in my GIA Diamond Grading binder.

Contains techy talk from Yanzter and others that was way over my head, something I bet that John Pollard could explain to us consumers.
"The summation of the ray energy over concentric rings that are equally spaced on the hemisphere permits quantification of the angular spectrum (accompanied by figure 3b). Huh? What is he talking about?

From a consumer perspective, I get that GIA triple EX has a wider range than AGS0, and then within AGS0
there is a bulls eye where the Super Ideal, H&A diamonds fall. I was willing to pay the premium for a custom Cut-to-Order CBI diamond, but completely understand if others prefer GIA triple EX and are hoping to find a Super Ideal among them.

There is something for everyone.

jck_nov_2004_ags0.jpg
 

denverappraiser

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Here's a copy of one from 2005. I'm not sure where it was originally published. I'll try and get a few more links tomorrow.

http://www.agslab.com/members/content/docs/Complete_Explanation_of_AGS_Cut_System.pdf

Here's one from the Optical Society of America, in 2003.

http://www.researchgate.net/publication/237337761_The_Optical_Design_of_Gemstones_Jos_M._Sasin

Whether or not Optics & Photonics news counts as a "general publication" is up to you and their circulation probably isn't all that great but I do think it's fair to call them peers.
 

denverappraiser

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drk14

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For anybody interested, here is a link to the GIA study (Moses et al., GEMS & GEMOLOGY, Vol. 40, No. 3, pp. 202–228):
http://diamondcut.gia.edu/pdf/cut_fall2004.pdf

This is a peer-reviewed* professional publication published quarterly by the GIA. These were the peer-review procedures/policies in 2004:
Manuscripts are examined by the editor-in-chief, editor, technical editor, and at least three reviewers. Authors will remain anonymous to the reviewers, and (unless specific permission is given) reviewers will remain anonymous to the authors. Decisions of the editors are final.
*For those not familiar with the term "peer review", this is scientific jargon that refers to the practice of submitting manuscripts for evaluation by one or more experts in the subject area of the article; typically, the editorial staff of the journal decide whether to accept or reject the manuscript based on the reviewers' comments, although commonly, the manuscript authors are given an opportunity to address any deficiencies noted by the reviewers before a final editorial decision is made.


The study in question recruited a total of 384 participants as "observers", of which approximately 40% were GIA staff, 40% were retailers, and 7% were consumers. Different groups of participants were asked to rate diamonds according to two or more out of 12 different observation criteria. Thus, a total of 70,842 data points (ratings) were collected, although the actual number of ratings ranged from 280 to 17,843 depending on the specific observation type.
 

drk14

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denverappraiser|1414355671|3773023 said:
Here's a Pricescope discussion from 2007 of the publication in the Journal of Optical Engineering although I haven't found the link to the original article.
[URL='https://www.pricescope.com/community/threads/scientific-recognition-for-ags-cut-grade-technology.71945/']https://www.pricescope.com/community/threads/scientific-recognition-for-ags-cut-grade-technology.71945/[/URL]
Is this the link you were looking for?
http://www.agslab.com/spie/spie_lo_res.pdf
 

MelisendeDiamonds

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denverappraiser|1414352180|3773011 said:
300 observers. 70,000 observations. Individual viewers said multiple things. He's correct that I made a typo in the above post.

Submitting to peer review is a matter of publishing your data, methodology, and results in a public way so that others can reasonably evaluate what you've done. There's no good way to count how many actually read it and, by the way, peer review doesn't make you right, it's just part of the scientific process. It's something GIA hasn't done. The data was kept secret and the metho"dology and algorithms leading to their conclusions were (and are) secret. That's not peer review, it's advertising.

Neil,

Claiming that GIA's cut grading research and data are "secret" is a gross exaggeration.

The 2004 article entitled "A Foundation For Grading Overall Cut Quality of Round Brilliant Diamonds" G&G Fall 2004 Pages 202 - 228 has an awful lot of information on data, definitions, methodology and certainly lays out in verbose detail their conclusions and how they reached them.

giaobservations_0.jpg

An argument can be made that the quality and objectivity of the peer review process and the standards of the editor at G&G is not up to the standard of say the academic journal where AGSL's foundation article was published in ( Optical Engineering 46(9) September 2007 093614-1 to 093614-25).

But supporting this argument requires careful reading of both articles (available online) and careful consideration of the fine details of both systems. Doesn't seem quite possible if your opinion remains that the details about the foundations of GIA's system are not published.

Much like AGSL, GIA is not going to disclose all the details of their cut grading formula and computer model. (No surprise the grading of both labs is proprietary to this day.)

I find this tangent has little to do with GIA India credibility or the original poster so perhaps this topic of discussion can be moved to its own thread.
 

Rockdiamond

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MelisendeDiamonds|1414366338|3773076 said:
.....snip

I find this tangent has little to do with GIA India credibility or the original poster so perhaps this topic of discussion can be moved to its own thread.

I agree- and it's a very interesting topic. I started a thread here:
[URL='https://www.pricescope.com/community/threads/gia-or-agsl-which-do-you-prefer-for-cut-grading-and-why.207339/']https://www.pricescope.com/community/threads/gia-or-agsl-which-do-you-prefer-for-cut-grading-and-why.207339/[/URL]
 
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