Today’s question is asked by James from Indianapolis. Fluorescence is a common property found in the majority of polished diamonds and I wanted to do this post so that the answer would benefit more readers.
Question: I was looking through your article on the differences in diamond grading labs while doing some research on your website. Basically, I had shortlisted a princess cut diamond that is certified by EGL at a local jeweler.
It is an E color, VS2, 1.34 carat diamond with slight fluorescence. In your article, you mentioned that clarity and color grading might probably be 1-3 grades lower if GIA/AGS had graded the same diamond. What about the grading for fluorescence? Are they lenient on this as well?
Answer: That’s a very good question. Like the generous grading for clarity and color, I think it is possible for an EGL diamond with slight fluorescence to be graded as a medium fluorescence. After all, grading is done by humans and is always subjected to a certain degree of errors. However, it is unlikely that the diamond would jump 2 notches to be graded with a very strong fluorescence.
While slight fluorescence has little impact on a diamond’s price, you should take note that medium or stronger fluorescence would drive the diamond’s value down.
Personally, I would stay away from diamonds graded by EGL because of the ‘questionable’ certification that comes along with them. Of course, if the price is right and if you feel good about the diamond, what I would recommend you to do is to make sure the jeweler has a good return policy and get it down in writing.
After buying the diamond, bring it down to a 3rd party appraiser/gemologist to get it examined. This way, you will get an unbiased 2nd opinion on the diamond and take things from there.
Hopes this helps,
Note: The phrasing of the question topic – “Grading of diamond fluorescence between labs” had been edited grammatically prior to being posted on the blog.