Discrepancies between lab certs--HRD & IGI

[canuk-gal]

Hello:

If this has been discussed before, I apologize--but please indulge me........

Today I viewed a very nice diamond, that had not one but two lab certificates; one from HRD and one from IGI. The HRD certificate appeared to be the original which also contained a more proportion information than did the IGI documentation.

As I compared the certs, I observed a difference between the grading for clarity; the HRD stating it was an SI1, while the IGI concluded it was SI1-SI2. The owner of the shop was out for lunch so I couldn''t ask him why there was a difference--and the salesgirl couldn''t account for it either. At any rate it begs the questions: why would one recerifiy a stone that comes from a reputable lab (is this not the case??), and given the discrepancy which cert. does one believe?

Also, what is one to make of color and clarity grades that are expressed on lab reports in ranges such as F-G, SI1-SI2, etc?


cheers--Sharon

 

[canuk-gal]

HI:

No ideas on this issue--or rather none that matter???? Thanks!!

cheers--Sharon

 

[Lord Summerisle]

I guess it was one of those subjective things… it twas a border line SI1 and 2… HRD took the stance to give it a clear SI1.. IGI decided to hedge their bets and mark it inbetween.

Colour… that’s open to whose viewing it I suppose.. its been said on here that unless its quite clear then colour grades can differ between ppl, and the lab by a grade… but the question should be asked as to why… is it a borderline case or not. If one graded F and the other I then there has been a mistake somewhere – as to where needs to be assessed.

Dunno why it would be sent to 2 labs… maybe the IGI was the initial rep.– and it was sent to HRD for a second opinion?

 

[denverappraiser]

Sharon,

Dealers will send a stone to an additional lab because they are hoping for better results. They normally will then discard the report from the lab that reports the inferior grade.

I was under the impression that IGI would only show a split grade if they examined a stone mounted and were therefore required to estimate some of the data. IGI has a service that they call an appraisal wherein they include a price that is supposedly comparable to those charged by some unnamed mythological (and very expensive) store. HRD won''t do this. Perhaps the dealer thought this number was somehow helpful to you in making your decision.

Neil Beaty
GG(GIA) ISA NAJA
Independent Appraisals in Denver

 

[Iceman]

Your going to find out that its all an opinion.

 

[canuk-gal]

Date: 2/11/2005 9:52:21 AM
Author: denverappraiser

Sharon,

Dealers will send a stone to an additional lab because they are hoping for better results. They normally will then discard the report from the lab that reports the inferior grade.

I was under the impression that IGI would only show a split grade if they examined a stone mounted and were therefore required to estimate some of the data. IGI has a service that they call an appraisal wherein they include a price that is supposedly comparable to those charged by some unnamed mythological (and very expensive) store. HRD won''t do this. Perhaps the dealer thought this number was somehow helpful to you in making your decision.

Neil Beaty
GG(GIA) ISA NAJA
Independent Appraisals in Denver

HI:

In hindsight, this seems logical--as I was immediately shown the IGI paperwork (looked more like an appraisal as you suggest--and yes the stone was then mounted): while the HRD cert. was tucked behind, but available for me to see.

Thing is, the split grading even for insurance purposes (appraisal) is dicy to me--with what would your stone be replaced should it need be: with a F S1 or 2 or G SI1 or 2? Furthermore, how does one determine what is reasonable to pay (negoitation is possible)--their is an obvious difference in cost between these four grading variables. BTW, I looped the stone and saw multiple scattered inclusions.

cheers--Sharon

 

[Lord Summerisle]

That’s to be expected… a grading of SI is far from the IF flawless grading… what matters is ‘can you see the inclusions without the aid of a Loupe?’ and if so… is it a problem… any you can see… does the person whose setting it (unless its already set) reckon they could hide the visible inclusions under a prong.

I think inclusions vary… an SI grading could be for a single large inclusion… or it could be a lot of small inclusions – invisible to the naked eye… but never the less, the amount of tiny inclusions add up to it being given the SI grading.

 

[denverappraiser]

Date: 2/11/2005 10

6:29 AM
Author: canuk-gal

Thing is, the split grading even for insurance purposes (appraisal) is dicy to me--with what would your stone be replaced should it need be: with a F S1 or 2 or G SI1 or 2? Furthermore, how does one determine what is reasonable to pay (negoitation is possible)--their is an obvious difference in cost between these four grading variables. BTW, I looped the stone and saw multiple scattered inclusions.

cheers--Sharon

Sharon,

I do not recommend anyone bind an insurance policy of any kind based on this type of report.

Neil Beaty
GG(GIA) ISA NAJA
Independent Appraisals in Denver