Measurements Not The Same

[shockhazzard]

I purchased a GIA certified diamond online and took it to Global Gemological Laboratory (GGL) in Bellevue WA to do the appraisel. GGL did a Comprehensive Diamond Report (with beautiful light analysis pictures of my diamond). I noticed that there is some differences in the GGL report vs GIA particularly the dimensions:
GIA says my diamond is:5.80-5.83x3.58
GGL says my diamond is:5.78-5.81x3.57
GIA says my diamond has Faint Flourescence
GGL says my diamond has No Flourescence

Is it possible that 2 different labs can measure a diamond so differently or is there some mistake? I am worried that the GGL lab report may be in error.

 

[homer_j]

I wouldn't be concerned by the disparity in the dimensions. Looks like a difference in the calibration or the tool used to measure, hand guage verses digital. 1-2 hundredths of a mm difference really isn't much. That's less than 1% difference. Not sure about the fluorescence, one of the resident experts will have to explain that.

 

[shockhazzard]

I believe GGL used digital equipment does GIA use digital or hand equipment to measure?

 

[homer_j]

I'm pretty sure hand equipment. I had some similar discrepencies during my appraisal.

 

[dimonbob]

It doesn't matter who used what equipment to do the measureing. Measuring gauges be they Leveridge, micrometer or sarin are not perfect. If you take your diamond to a third lab, you will will get a third set of measurements. One of these days they will get more exact measureing equipment but not yet.
As far as the flourescence goes, I would guess that GIA is correct here although they have been wrong. If you are looking into a dark box with a uv light above to get flourescence sometimes you can mistake reflection as flourescence and miscall it. Who knows? One of them made a small mistake. Faint flourescence is no big deal. Almost everything in diamond grading is SUBJECTIVE. That means that two different human experts can call the same thing two different things. None of the Labs are right all of the time and never will be.

 

[Mara]

DB has an excellent point....grading is done by humans, even humans working the machines, therefore human error. The differences in your dimensions are miniscule. No worries. Faint vs. none is nothing to worry about either. Good luck!

 

[shockhazzard]

Thanks so much for the explanation as to why my measurements have slight variation between reports, you have put my concerns to rest.

I would also like to say that I had a great experience with the GGL Lab in Bellevue Wa. I called GGL and they were very accomodating and had me bring my diamond in for evaluation the same day I received it from Affordablediamondsonline.com. The staff as GGL were friendly and were helpful in answering my questions. They did a complete evaluation of my diamond(while I watched through a window into their lab) with mapping and light analysis to evaluate the degree of Brilliance, Dispersion, and Scintillation. My diamond got the highest score of Maximum in all categories. I was told it is a Triple 0. The report cost $60 and comes with beautiful color pictures of my diamond. I paid $3600 for the diamond and it was appraised at $6400.

I have a Round 0.74 carot vvs2 color E crown angle 34.2 pavil angle 40.6 Depth 61.1 Table 56. This diamond really shines like nothing I have seen in the retail stores.

Thankyou Affordablediamondsonline.com for finding me a great diamond when my first choice was no longer available. I purchased on Thursday and it arrived by FedEx Friday morning. Having it set tomorrow, wish me luck.

 

[newenglandgemlab]

Hi,

Have you noticed the change in terminology being used for fluorescence (AGS reports)? It is correct to use negligible for fluorescence since a little fluorescence will have no effect on the value. This will make it a little less confusing to the consumer. Very faint is sometimes a tough call. Cindy