Thoughts on GIA reports

[lali0020]

I was talking with someone about diamonds that works in the industry about a GIA report and they were trying to say that without a Megascope and Colorimeter report, they wouldn't trust the reports even from GIA. Their basis was from the fact that the percentages on the report read 58.9 total depth, 3% girdle, 13.0% crown and 42.5% pavillion. She claimed that since these numbers don't add up, that the problems exist with the report and they could be grade bumping on things like color and clarity too. Does anyone else have experience with this? Am I crazy to be considering buying a diamond that doesn't have a colorimeter and megascope report to verify the GIA one??

Also I asked what a typical price for a well cut 1 ct. H, SI2 diamond should be and she said $8000 which seemed super high from what I've seen. Does that mean I'm looking in the wrong places or she is way too restrictive on purchasing standards. Thanks.

 

[slg47]

GIA is the standard...so I would trust the GIA report. as far as pricing, you can do a search under resources--> diamond search to see pricing for comparable specs.

 

[ChrisES]

Hey there,

I have been lurking for a couple of weeks, but your post convinced me to create an account to help you out.

From my research I've learned that GIA percentages can not "add up" buy as much as 2%.....I can't recall exactly where I saw this, it was either here on PS or at GoodOldGold. If I recall correctly, it's because GIA doesn't account for painting and digging the girdle, and they also round their numbers a bit. Your figures are within .4% of adding up, so I would not be concerned at all. As I understand it, this is a known issue with GIA reports and not evidence of any "grade bumping."

 

[lali0020]

Thank you. That makes me feel much better. I'm not sure why this other person would push me into thinking I needed a megascope of colorimeter when I have a GIA report. They pointed to the report of some "problems" found at GIA in the past and started to make me nervous that I might be buying a diamond that had been adjusted or bumped and therefore could be more of a J, I1 and not the H, SI2 I thought I was getting. I compared the diamond next to a J color GIA stone and could see it was better but it is easy to get distracted by what others are saying when you are paying so much for something you don't feel 100% knowledgable about.

 

[Rockdiamond]

Interesting- usually the "punch line" of a seller who's trashing GIA is to suggest the buyer go for an EGL graded diamond.

GIA is what every diamond cutter/dealer uses to fix value.
A colorimeter is not acceptable for color grading- again, speaking of dealers and cutters who really have to have accurate info. Stones must be graded by trained eyes.

 

[ChrisES]

Here on PS, where I've seen criticism of GIA has been regarding their cut evaluations and in particular the imprecision of the rounded figures. I'm not aware of any significant, informed criticism of their color or clarity grades.