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Miss Jewels

Diamond Grading vs Moissanite

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Miss Jewels

I recently had all my moissanites sent to The Gem Lab for certification and valuations.

 

I was very surprised when I received them back and saw difference between the new cert description vs the descriptions as advertised when I purchased them

 

According to Mr Rothon, accredited senior Gemmologist (AGA), "one can't and shouldn't grade Moissanite as a diamond, because it is not a diamond. It gets graded as a normal gemstone."

 

While certified diamonds are graded on color and can be compared with one another, moissanite stones are not graded on color. (web reference diamonds vs moissanite)

 

So while we all purchase moissanite on-line, thinking we are getting a specific colour - this is not the case. Most of the stones will have an understone - which means the stone will then be graded as such colour. So if a stone has a yellow undertone, it will be graded as light brown.

 

We also need to bear in mind that moissanite as purchased on-line, are not natural moissanite, but synthetic moissanite, and should actually be described as such. Natural moissanite are very rare and if available, are only tiny stones, normally measuring in under 0.25ct. All other moissanite are synthetic.

 

All my stones, be it gemstones, diamond or moissanite, are sent to a gemmologist at my cost, before selling. This is so that I can offer my buyers absolute peace of mind in what they are puchasing. They also get the gem report free of charge with their purchase.

 

Even some of the other valuable pieces I have purchased on-line have differred vastly in colour and clarity since being returned from the Gem Lab. Not ideal for me but now at least I know what I have purchased.

 

Feel free to contact me regarding any info as I have quite a lot of info received from the gemmologist and I have also completed a few courses with the said gemmologist.

 

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Serthentia Sales

Hi Miss Jewels. Interesting read. However, I feel I must point something out as the inference is that some sellers are intentionally misrepresenting their stones. While this may be true in some cases, it is not necessarily the case even if your gemologist grades the stone differently to the description given. There are often vast differences in grading of the same stone even by different professional gem labs. Please see the below copied from diamonds.net:

 

 

 

No two diamonds are alike and it seems neither are their grading certificates. A survey by RapNet – the Rapaport Diamond Trading Network, found significant differences between laboratories grading the same diamond.

 

While there is a common language used in the grading of diamonds, there are clear inconsistencies in the use of that language, concluded Saville Stern, chief operating officer of RapNet. Stern oversaw the study and presented its findings at the fourth annual Rapaport Diamond Certification Conference in Las Vegas on June 2.

 

The RapNet team sent 10 diamonds, ranging in size from 0.33 carat to 1.62 carats, and of varying qualities to six different labs for grading to assess the consistency, or lack thereof, of their respective reports. The diamonds were sent to the GIA, IGI, HRD, EGL USA, EGL Israel and EGL Hong Kong.

 

The results were analyzed according to the strictness of grading and the price those goods would achieve on RapNet. The survey is a precursor to a more in-depth study currently being conducted by RapNet.

 

While the results on some of the sample diamonds indicated some consistency in grading, there were significant variations on others. (See the full results in the tables at the end of this article).

 

Typically, one color or clarity grade variation would be considered reasonably acceptable in the market. On some of the diamonds, the labs were fairly consistent providing only slight variations in color and clarity.

 

More dramatic differences were apparent in other stones. For example, a 1.01 carat stone was graded as K color, SI1 clarity by both GIA and IGI, whereas EGL Israel graded it a G, VS1, a difference of 4 color grades and 2 clarity grades. A different 1.01 carat diamond was found to be F, I1 by GIA and IGI, but was graded as D, SI1 by EGL Israel and EGL Hong Kong, while HRD graded it to be F, SI2.

 

You can ready the full story at http://www.diamonds.net/News/NewsItem.aspx?ArticleID=43417

 

 

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