shape
carat
color
clarity

GIA certified Appraiser disagrees with the GIA report?

Status
Not open for further replies. Please create a new topic or request for this thread to be opened.

kohdy

Shiny_Rock
Joined
Mar 9, 2007
Messages
351
I recently had my center stone reset in a beautiful Ritani setting. I then took it to a GIA certified appraiser (Carole Richbourg) in my area that I found on the PS for an updated appriaisal. Everything else seems to match except for the fluorescence. On my GIA certificate, it is noted that there is NO fluorescence, but the appraiser informs me that it really is moderate fluorescence, which in her expert opinion should not affect the price of my diamond. I actually witnessed the fluorescence with my own eyes in her office! I have not noticed any milkiness or cloudiness in my diamond in the sun or under any other lighting in the past 5 years and I do look at my diamond FREQEUNTLY all throughout the day!!! Should I be concerned? Is it also common for GIA certificate to be a little off? I am a bit confused!

You can look up my diamond if you wish: GIA certificate # 12141033
Otherwise, here is the stated specs on my certificate:
Square modified brilliant, 1.81ct, D, VS1, Excellent poliish, Good symmetry, very thin to slightly thick girdle, no culet or fluorescence (apparently this is false...
8.gif
)

Mylittleprincess.JPG
 

oldminer

Ideal_Rock
Trade
Joined
Sep 3, 2000
Messages
6,695
There is no excuse for it, but a lab employee at the GIA once told me on the telephone that if there was less UV fluorescence than their "slight" test stone that they put "none" on the report. I was surprised and upset by this really dumb appraoch to truth in selling and grading, but if the GIA does it that way then it must be right!
29.gif
29.gif


Anyway, I often differ on their assessment of the level of UV fluorescence and try to make as little waves as possible over it unless it is of importance to value or re-identification. If I see any, but very liitle we use "negligible". If I see none I put "none" or "inert" depending on what my fingers type out. I made master sets for blue and yellow UV fluorewcence for my staff to use probably 20+ years ago. I am sure they are not identical to what GIA uses, but at least I have a set of physical standards we use and no one outside the GIA lab has ever seen what standards they use. Background lighting also has an effect on subjective strength of visual UV fluorescence.

My educated advisor tells me that all diamonds react, fluoresce to UV light, but that only some react in the visible spectrum. The visible reaction is what is graded, but all diamonds fluoresce......
31.gif
 

decodelighted

Super_Ideal_Rock
Joined
Jul 27, 2005
Messages
11,534
I wouldn't worry about it ... sounds like maybe an honest mistake? Labs screw up too sometimes.

Fluor isn't DETRIMENTAL to a stone unless it makes it cloudy or oily and I've heard that's VERY rare. If you've never noticed it - and the stone is gorgeous - and it doesn't affect value ... just brush it off as odd but uneventful.
 

Sparkles22

Brilliant_Rock
Joined
Apr 20, 2006
Messages
1,130
Date: 5/2/2007 2:02:10 PM
Author: kohdy
If you wish to view photos of my ring, you can view quite a few on another topic that I started: https://www.pricescope.com/community/threads/my-ring-is-finally-here.61305/

Just for fun... Presenting Miss Muffin: my little baby! I have three, and she is the youngest of the three!!!
9.gif
Sorry can''t help you out on the grading question.. but OMG what a GORGEOUS kitty!!!!!!!!!! How old is she? Don''t the others feel left out their pictures aren''t posted?
 

kohdy

Shiny_Rock
Joined
Mar 9, 2007
Messages
351
Date: 5/2/2007 3:09:12 PM
Author: oldminer
There is no excuse for it, but a lab employee at the GIA once told me on the telephone that if there was less UV fluorescence than their ''slight'' test stone that they put ''none'' on the report. I was surprised and upset by this really dumb appraoch to truth in selling and grading, but if the GIA does it that way then it must be right!
29.gif
29.gif


My educated advisor tells me that all diamonds react, fluoresce to UV light, but that only some react in the visible spectrum. The visible reaction is what is graded, but all diamonds fluoresce......
31.gif
Thank you David for all the information you have provided. I feel somewhat better but I am honestly surprised. I specifially looked for a diamond with no fluorescence because I knew I wanted a D colored diamond and I didn''t want the fluorescence to affect the color grading of my diamond. I hear that fluorescence can often make the diamonds appear whiter? I guess I am not too bummed, though, knowing that all diamonds fluoresce to a certain degree. My stone is very special to me and nothing (not even the slightly midguided GIA report) is going to change that.
5.gif


Decodelighted, I will definitely take your advice and brush it off as if nothing has ever happened. I think it''s going to be easier than I thought.
4.gif
I am already done with the initial shock and am dealing with it like an adult.
2.gif


Sparkles! Thank you for the compliments on my kitty! Muffin is almost 3-she''s turning 3 this August. The other one you see on my avatar (or display image) is Bobo, my second child, who by the way is not photogenic at all! He is absolutely gorgeous and is turning 4 this month! The oldest one I have is named Cherry (a black and brown tabby with long hair) and is about 7 years old-her estimated age at the time of adoption was 2 but it was only an estimation. All three were adopted from local animal shelters.
1.gif
I realize that my kitties could get jealous at times, so I am going to try to change my avatar to Cherry''s picture at some point. Hopefully rotating their pictures will help them feel better about the whole issue? Anyway, thank you again for noticing and commenting on my babies!!!
2.gif
 

Nicrez

Ideal_Rock
Joined
Jan 21, 2004
Messages
3,230
David is right. A majority of the labs use a FAINT, MEDIUM, STRONG diamond set to verify. And yes, like GIA I know of a few who write none when it should be "Negligable" as David says. But as GIA is the ring leader, so go the lemmings. Kudos Dave for being honest! But consider many people get nervous (like yourself) at the words "fluorescence" and IMO, if it's not an investment stone, and it's not SB with a milky appearance, I don't care one iota, except that it tells me one more way to determine my stone from others. It's a property of a piece of carbon formed in the earth so long ago. It has it's characteristics, and the scare of FL is silly...

Go on your merry way and feel comfortable that you have a lovely stone, regardless... I assume princess cut, because of the depth and crown...?
 

Sparkles22

Brilliant_Rock
Joined
Apr 20, 2006
Messages
1,130
Muffin is almost 3?! She has such a baby face (I thought for sure she was a kitten still)! Awww Bobo isn''t photogenic, well he is absolutely cute in your avatar pic! What kind of cats are those... if I had to guess Muffin= ragdool, Bobo = simamese? They are sooooo cute!!!!! I love kitties!!!
 

kohdy

Shiny_Rock
Joined
Mar 9, 2007
Messages
351
Date: 5/2/2007 5:38:14 PM
Author: Nicrez
David is right. A majority of the labs use a FAINT, MEDIUM, STRONG diamond set to verify. And yes, like GIA I know of a few who write none when it should be ''Negligable'' as David says. But as GIA is the ring leader, so go the lemmings. Kudos Dave for being honest! But consider many people get nervous (like yourself) at the words ''fluorescence'' and IMO, if it''s not an investment stone, and it''s not SB with a milky appearance, I don''t care one iota, except that it tells me one more way to determine my stone from others. It''s a property of a piece of carbon formed in the earth so long ago. It has it''s characteristics, and the scare of FL is silly...

Go on your merry way and feel comfortable that you have a lovely stone, regardless... I assume princess cut, because of the depth and crown...?
Thank you Nicrez. I appreciate your advice. And yes, it is a princess stone. I know you''re not so crazy about princess cut stones (from what I have read on your postings
9.gif
) but I am oddly only drawn to square shaped stones. My husband originally proposed with a RB, but it took me a whole year to get my nerves together and ask him for what I really wanted. I don''t ever regret my decision for the switch, either!
2.gif
But seriously, thank you for taking the time to respond to this post because I am now more at ease.
5.gif
I trust your opinion.

Sparkles! Both Muffin and Bobo are Siamese mixes according to the vets I have seen. But who knows? Muffin could be a ragdoll like you suggested!
2.gif
Muffin is a lilac point, medium haired and Bobo is a seal point, short haired. They are basically mutts, though! haha...
9.gif
Yeah... Muffin still has a kitty face. She''s really cute and full of personality. I think she thinks she''s a puppy for the most part! In fact, she almost looked like a pomeranian puppy when she was a little kitty!
6.gif
 

Sparkles22

Brilliant_Rock
Joined
Apr 20, 2006
Messages
1,130
One of my cats has a baby face and everytime she makes me mad I just can''t be. I take one look at that face and I think awww poor little kitty (tricks me everytime!). The blue eyes are beautiful! Our orange tabby had blue eyes until he was like 9 months or so. Based on his personality and everything the vet though he might have some siamese in him. His eyes have since turned a light yellow, but his playful personality is still very much there. I believe he will be 4 in July.
 

kohdy

Shiny_Rock
Joined
Mar 9, 2007
Messages
351
Date: 5/2/2007 6:14:10 PM
Author: Sparkles22
One of my cats has a baby face and everytime she makes me mad I just can't be. I take one look at that face and I think awww poor little kitty (tricks me everytime!). The blue eyes are beautiful! Our orange tabby had blue eyes until he was like 9 months or so. Based on his personality and everything the vet though he might have some siamese in him. His eyes have since turned a light yellow, but his playful personality is still very much there. I believe he will be 4 in July.
Sparkles, do you have pictures of your babies that you can share with me? And I know exactly what you are saying about the baby face... I just cannot get mad at Muffin even when she starts biting my newly purchased bags and what not! Haha... at least she stops when I say NO!
2.gif


Hey, I have an idea! Why don't we start a topic in Hang Out about our kitties?!? You can start it by posting the photos of your babies, and I will follow up on it when I get home tonight. I have some photos of all three of mine that I can post! Just a suggestion!!!
2.gif
 

Sparkles22

Brilliant_Rock
Joined
Apr 20, 2006
Messages
1,130
Date: 5/2/2007 6:20:49 PM
Author: kohdy

Date: 5/2/2007 6:14:10 PM
Author: Sparkles22
One of my cats has a baby face and everytime she makes me mad I just can''t be. I take one look at that face and I think awww poor little kitty (tricks me everytime!). The blue eyes are beautiful! Our orange tabby had blue eyes until he was like 9 months or so. Based on his personality and everything the vet though he might have some siamese in him. His eyes have since turned a light yellow, but his playful personality is still very much there. I believe he will be 4 in July.
Sparkles, do you have pictures of your babies that you can share with me? And I know exactly what you are saying about the baby face... I just cannot get mad at Muffin even when she starts biting my newly purchased bags and what not! Haha... at least she stops when I say NO!
2.gif


Hey, I have an idea! Why don''t we start a topic in Hang Out about our kitties?!? You can start it by posting the photos of your babies, and I will follow up on it when I get home tonight. I have some photos of all three of mine that I can post! Just a suggestion!!!
2.gif
Sorry I didn''t mean to hijack your thread
7.gif
. I posted some pics of them in firegoddess'' thread earlier today https://www.pricescope.com/community/threads/feral-and-stray-cats.61246/page-3 (Fraidy cat is the baby face). I would love to see pictures of your babies!! My orange tabby likes to lick plastic bags, what a weirdo!
 

RockDoc

Ideal_Rock
Joined
Aug 15, 2000
Messages
2,509
There are SUBJECTIVE conclusion made gemologically and there are objective calls.

When GIA says "None" and the stone is moderately fluorescent, IMO that crosses the line between subjectivity and objectivity.

Cause? Carelessness or may be even negligence.

I believe that credit is due Adamasgem ( Marty Haske ) for advising AGS of this and they heeded the change of using the terminology of "negligible" which is obviously more accurately informative and correct to do.

GIA also reports "profile to actual proportions" when in fact we know it isn''t. They are rounded up averages. They seemed to have corrected this in the past, but I see that recently that phrase is on newer reports.

I guess how seriously you want to consider the above is an indivual relier''s choice, being he is the one doing the relying.

For me, I take things at their word. I hate to use a strong opinion such as intentionally fraudulent, but I take reports from the "authority" pretty seriously on a level of truthful accurate disclosure to people who will rely on what is stated in the report.

It just appears to me that GIA is rather stubborn about change, and AGS is doing the exact opposite.

Rockdoc
 

kohdy

Shiny_Rock
Joined
Mar 9, 2007
Messages
351
Date: 5/2/2007 6:28:11 PM
Author: Sparkles22

Sorry I didn''t mean to hijack your thread
7.gif
. I posted some pics of them in firegoddess'' thread earlier today https://www.pricescope.com/community/threads/feral-and-stray-cats.61246/page-3 (Fraidy cat is the baby face). I would love to see pictures of your babies!! My orange tabby likes to lick plastic bags, what a weirdo!
Oh, don''t be Sparkles! I am actually glad that you did because my babies need attention!
9.gif
And if there is one thing that I could possibly like more than diamonds, it is CATS! Wait... I think it should be my hubby, and then my cats...
9.gif
I will definitely check out your thread! I am now very excited!!!
36.gif
 

RockDoc

Ideal_Rock
Joined
Aug 15, 2000
Messages
2,509
GIA CERTIFIED APPRAISER?????????????????

NO SUCH TITLE FROM GIA

GIA states that they certify NOTHING and NO ONE.
( GIA has a non diploma course in INSURANCE Appraising, but don''t now) . In short GIA, teach gemology / not valuation

Here are the groups that do :

AGS Has Certified Gemologist, Certified Gemologist Appraiser and Independent CGA titles

ISA has the Certified Appraiser of Personal Property Designation ( CAPP )

ASA has Master Gemologist Appraiser Designation

There are a few other - but above are the "important certification titles"


APPRAISE THE APPRAISER! Beware of overstatement of credentials as it is commplace.

Rockdoc
 

kohdy

Shiny_Rock
Joined
Mar 9, 2007
Messages
351
Date: 5/2/2007 6:30:29 PM
Author: RockDoc

When GIA says ''None'' and the stone is moderately fluorescent, IMO that crosses the line between subjectivity and objectivity.

For me, I take things at their word. I hate to use a strong opinion such as intentionally fraudulent, but I take reports from the ''authority'' pretty seriously on a level of truthful accurate disclosure to people who will rely on what is stated in the report.

It just appears to me that GIA is rather stubborn about change, and AGS is doing the exact opposite.

Rockdoc
Very interesting... I have always insisted on GIA reports because I thought they were the most reliable. I just assumed that everything on that report was completely accurate, but it is a little disappointing to know that there were some misleading information. As Nicrez has mentioned, my stone was not purchased for the purpose of investment and I do not notice the effects of fluorescence on a daily basis, so I will just have to get over this incident. However, in the future, I might insist on AGS reports with the infomation you have given me. Even if it was an honest mistake or negligence on their part, I eventually ended up with a diamond that I would not have purchased had I known the truth. I think I would have felt better if the FL in my diamond was faint, but it is moderate according to the appraiser. Oh well...
8.gif
 

kohdy

Shiny_Rock
Joined
Mar 9, 2007
Messages
351
Date: 5/2/2007 6:38:46 PM
Author: RockDoc
GIA CERTIFIED APPRAISER?????????????????

NO SUCH TITLE FROM GIA

GIA states that they certify NOTHING and NO ONE.
( GIA has a non diploma course in INSURANCE Appraising, but don't now) . In short GIA, teach gemology / not valuation

Here are the groups that do :

AGS Has Certified Gemologist, Certified Gemologist Appraiser and Independent CGA titles

ISA has the Certified Appraiser of Personal Property Designation ( CAPP )

ASA has Master Gemologist Appraiser Designation

There are a few other - but above are the 'important certification titles'


APPRAISE THE APPRAISER! Beware of overstatement of credentials as it is commplace.

Rockdoc
Oops! I could have been mistaken. She states that she is a GIA alumni. I have no idea what that means..
3.gif


"Carole holds a Graduate Gemologist (GG) title from the Gemological Institute of America (GIA), and a Certified Gemologist Appraiser (CGA) title from the American Gem Society. Carole is also a candidate member in good standing of the American Society of Appraisers (ASA). See her list of certifications and courses."

Above is what is stated on her website. I found her on the resources section of PS.
 

RockDoc

Ideal_Rock
Joined
Aug 15, 2000
Messages
2,509
Don''t be upset with "moderate fluoresence" Sometimes fluorescence "helps the appearance" of the stone. This is usually true for moderate, faint, weak etc. stones.

As far as using GIA alumni as a credential, it means she has a MINIMUM of one class, at GIA. To be fair she also could have taken many classes. Did she tell you she was a GRADUATE GEMOLOGIST? That is the official terminology of GIA''s highest gemological courses. ( the sort of disappointing standard is once you are a GG, you are one forever.

Compare that to AGS where you are tested each year in order to use he credential, and AGS also requires periodic color vision examinations (every four years, and every two years once you are older ( I think 50 or 55 is the age).

On her appraisal she should have included a CV/ resume of her educational credentials along with other backgroud information as to appraisal ( valuation) societies and classes she has completed, along with continuing education. Her employment experience should be listed too.

Rockdoc
 

WinkHPD

Ideal_Rock
Trade
Joined
May 3, 2001
Messages
7,516
Date: 5/2/2007 6:45:25 PM
Author: kohdy

Date: 5/2/2007 6:38:46 PM
Author: RockDoc
GIA CERTIFIED APPRAISER?????????????????

NO SUCH TITLE FROM GIA

GIA states that they certify NOTHING and NO ONE.
( GIA has a non diploma course in INSURANCE Appraising, but don''t now) . In short GIA, teach gemology / not valuation

Here are the groups that do :

AGS Has Certified Gemologist, Certified Gemologist Appraiser and Independent CGA titles

ISA has the Certified Appraiser of Personal Property Designation ( CAPP )

ASA has Master Gemologist Appraiser Designation

There are a few other - but above are the ''important certification titles''


APPRAISE THE APPRAISER! Beware of overstatement of credentials as it is commplace.

Rockdoc

Oops! I could have been mistaken. She states that she is a GIA alumni. I have no idea what that means..
3.gif


''Carole holds a Graduate Gemologist (GG) title from the Gemological Institute of America (GIA), and a Certified Gemologist Appraiser (CGA) title from the American Gem Society. Carole is also a candidate member in good standing of the American Society of Appraisers (ASA). See her list of certifications and courses.''

Above is what is stated on her website. I found her on the resources section of PS.

It is good that she is not holding herself out as a GIA certified anything, since what she has on her listing is correct, and permissible under the GIA rules and regs. If she was stating that she was GIA certified they would come down on her like a ton of bricks when they found out about it.

Now if they were only as diligent about their terminology...

Wink who agrees with Old Miner and Rock Doc about their "laxity" in describing fluorescence.
 

RockDoc

Ideal_Rock
Joined
Aug 15, 2000
Messages
2,509
Date: 5/2/2007 6:58:26 PM
Author: Wink

Date: 5/2/2007 6:45:25 PM
Author: kohdy


Date: 5/2/2007 6:38:46 PM
Author: RockDoc
GIA CERTIFIED APPRAISER?????????????????

NO SUCH TITLE FROM GIA

GIA states that they certify NOTHING and NO ONE.
( GIA has a non diploma course in INSURANCE Appraising, but don''t now) . In short GIA, teach gemology / not valuation

Here are the groups that do :

AGS Has Certified Gemologist, Certified Gemologist Appraiser and Independent CGA titles

ISA has the Certified Appraiser of Personal Property Designation ( CAPP )

ASA has Master Gemologist Appraiser Designation

There are a few other - but above are the ''important certification titles''


APPRAISE THE APPRAISER! Beware of overstatement of credentials as it is commplace.

Rockdoc


Oops! I could have been mistaken. She states that she is a GIA alumni. I have no idea what that means..
3.gif


''Carole holds a Graduate Gemologist (GG) title from the Gemological Institute of America (GIA), and a Certified Gemologist Appraiser (CGA) title from the American Gem Society. Carole is also a candidate member in good standing of the American Society of Appraisers (ASA). See her list of certifications and courses.''

Above is what is stated on her website. I found her on the resources section of PS.


It is good that she is not holding herself out as a GIA certified anything, since what she has on her listing is correct, and permissible under the GIA rules and regs. If she was stating that she was GIA certified they would come down on her like a ton of bricks when they found out about it.

Now if they were only as diligent about their terminology...

Wink who agrees with Old Miner and Rock Doc about their ''laxity'' in describing fluorescence.

Needless to say I commented based on what the OP stated.

It is patentily obvious from the above that Carole is exceptionally well educated, qualified and certainly diligent.

Rockdoc
 

JohnQuixote

Ideal_Rock
Joined
Sep 9, 2004
Messages
5,212
I''ve heard different reports about how far from the UV source the diamond is when the grade is set. Anyone know? That may account for differences between the lab and others.

Regarding terminology, GIA reports fluorescence as ''none, faint, medum, strong or very strong.'' Before 2003 the AGS used the terms ''inert, faint, medium, strong or very strong.'' In 2003 they stopped using inert & faint and replaced them with ''negligible.''
 

elmo

Brilliant_Rock
Joined
Jun 18, 2003
Messages
1,160
Date: 5/2/2007 8:29:12 PM
Author: JohnQuixote
I've heard different reports about how far from the UV source the diamond is when the grade is set. Anyone know? That may account for differences between the lab and others.
I know what you're saying (closer to source means more response) but it shouldn't matter if the stone being graded is sitting next to the lab's reference stones, should it? i.e. The reference stones will be similarly affected because they're the same distance from the source as the stone being graded.

Edit: Actually, in this case (none vs. appraiser seeing some) I see what you mean John - the appraiser isn't using reference stones and may not be using the same source as the lab at the same distance. It could account for the difference.
 

Nicrez

Ideal_Rock
Joined
Jan 21, 2004
Messages
3,230
I think the easiest explanation for the differences in fluorescence would the the strength of the UV bulb and how strong of a light it emits. Many a time have I seen a stone that was faint or negligible but put under another UV source it's suddenly medium or strong. Standardizing the strength of bulbs will be difficult as they near their death, but being in a lab that is ISO certified and keeps a consistancy of UV light sources is always better. But of course, who is to say that another lab may not have strong or lighter bulbs?

Let's be realistic, when out on the road, how many people set up a lightbox to lab standards? No one. And if it's strong or medium, that's when we really notice and start consulting the RAP sheet. To me, I would do as David says and be as accurate as possible when in a lab and testing a stone, but keeping in mind that there is no way to do testing without a certain level of variance. If the variance does not really affect price, durability or appearance issues then I would let it go as a consumer.

GIA should really be more proactive in mentioning the accurate fluorescence, as they are about all the other minute details of a stone as they are now trying to do...
20.gif


But as a consumer, I say let it be. Kodhy, your stone is absolutely lovely! I suppose it's no suprise I am not generally a fan of princess cuts, but that is only because of the monsters I have seen on 47th street...
7.gif
Your stone looks beautiful in that setting i hope you enjoy your new bauble!
 

adamasgem

Brilliant_Rock
Joined
May 23, 2003
Messages
1,338
Date: 5/2/2007 8:29:12 PM
Author: JohnQuixote
I''ve heard different reports about how far from the UV source the diamond is when the grade is set. Anyone know? That may account for differences between the lab and others.

Regarding terminology, GIA reports fluorescence as ''none, faint, medum, strong or very strong.'' Before 2003 the AGS used the terms ''inert, faint, medium, strong or very strong.'' In 2003 they stopped using inert & faint and replaced them with ''negligible.''
I believe I covered that in http://www.adamasgem.org/giafluor.html

It is well documented there, the historical change regarding a little sloppiness in grading techniques suggested by GIA..

"Negligible" came about, I believe, after I filed a complaint (to no avail) with the FTC about GIA''s Clintonesque use of the word "none", and pointed out to the lab that "inert" was just as bad technically as most diamonds will have some amount of UV sensitivity, and that the the visibility of the fluorescence depends on the amount of UV you pump in, either by a stronger initial source or holdong the stone closer to the source, or in the case of flurescent tubes, where along the tube you test. Based on photmetric tests I have conducted the strongest UV output appears to be in the center of the tube, and tapers off toward te ends.

Tom Tashey at PGS (old EGL-LA) was probably the first in the industry to use a UV absorbing "film", and then I suggested to people to use a polycarbonate (Lexan), to block UV. Tom deserves the full credit for initially pushing and questioning GIA on fluorescence when he had GQI, and I remember an article that Tom wrote in his newsletter, that GIA responded to in typical (for the time) GIA doubletalk that infuriated me, as I remember.

It was after this, that I did the historical research and posted the article on my site.

GIA''s winter 1997 G&G article on fluorescence was the starting point for an about face on color grading of diamonds, followed shorthly therafter by a color science technical journal article in October 1998 on the Tavernier diamond showing the effect on color of blue fluorescence on a colored diamond, diametrically different than what they said in the Winter 1997 regarding colorless diamonds. The physics are the same, and can be shown easily with a spectrophotometer.

See Winter 1997 G&G
http://www.gia.edu/gemsandgemology/27540/free_article_downloads.cfm
 

adamasgem

Brilliant_Rock
Joined
May 23, 2003
Messages
1,338
Date: 5/3/2007 8:39:35 AM
Author: elmo

Date: 5/2/2007 8:29:12 PM
Author: JohnQuixote
I''ve heard different reports about how far from the UV source the diamond is when the grade is set. Anyone know? That may account for differences between the lab and others.
I know what you''re saying (closer to source means more response) but it shouldn''t matter if the stone being graded is sitting next to the lab''s reference stones, should it? i.e. The reference stones will be similarly affected because they''re the same distance from the source as the stone being graded.

Edit: Actually, in this case (none vs. appraiser seeing some) I see what you mean John - the appraiser isn''t using reference stones and may not be using the same source as the lab at the same distance. It could account for the difference.
Bulbs age and also burn out and "sometimes" it isn''t noticed... even on GIA "master" stones

When one uses the small GIA 4W black viewing box GIA with the removeable LW/SW light, if you put the light back on the box in the wrong position you can wind up changing the distance of the LW or SW soucre to the stone becuase the "light" is sitting at an angle to the base of the viewing box..and everything is highly non linear in the process.

Also the the UV distribution in the box and from a tube is NOT uniform, so technique matters as well as the viewer''s color sensing deficiencies, if they know them.

It is NOT a "calibrated" procedure..
 

kohdy

Shiny_Rock
Joined
Mar 9, 2007
Messages
351
Wow... Thanks to everyone that is contributing to this forum, I am learning so much! I now have a better understanding about fluorescence than ever before! But that is not to say that I am now an expert!
9.gif
There is still so much more to be learned...
4.gif


Nicrez, thank you for your compliment on my stone. That just about made my day. I have seen numerous postings done by you in the past month or so, and you are basically turning into my idol!
2.gif
I love your honest approach on all matters!

adamasgem, thank you for the article. I enjoyed reading it!
5.gif

THANK YOU EVERYONE for educating me. Please feel free to post more so that I can continue to feed into my brain!!!
36.gif
 

kohdy

Shiny_Rock
Joined
Mar 9, 2007
Messages
351
Date: 5/2/2007 6:55:53 PM
Author: RockDoc
As far as using GIA alumni as a credential, it means she has a MINIMUM of one class, at GIA. To be fair she also could have taken many classes. Did she tell you she was a GRADUATE GEMOLOGIST?

On her appraisal she should have included a CV/ resume of her educational credentials along with other backgroud information as to appraisal ( valuation) societies and classes she has completed, along with continuing education. Her employment experience should be listed too.

Rockdoc
Hello Rockdoc,

I could have sworn that I posted an answer to your question, but I must not have...
6.gif
First off, THANK YOU for taking your precious time to explain a few things. I really do appreciate it. No, Carole did not claim that she was a graduate gemologist. I am so glad that everyone now seems to understand that it was my poor wording that got everyone so fired up about her credentials! Carole was truly wonderful and a joy to work with! I also see that she has taken several courses with GIA on her CV/resume that was attached to the appraisal.
2.gif
 
Status
Not open for further replies. Please create a new topic or request for this thread to be opened.
Be a part of the community Get 3 HCA Results
Top