Diamond District

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The NYC Diamond District runs a strict battery of test on all of the diamonds that pass through. One of the things that we test for in our labs is the highly misunderstood phenomenon called Fluorescence. This is when trace minerals within the diamond cause it to react under our special ultraviolet lights. People used to believe that any diamond with fluorescence was not as valuable as one without. It was seen to be a negative occurrence for a diamond. We now know that this is not always the case.

The most common color exhibited by fluorescence is blue. The blue fluorescence in an otherwise perfect diamond can actually improve the appearance of the diamond by making it clearer that it actually is. In other words, a certain amount of blue fluorescence improves the clarity of some diamonds, in particular, those with a lower than perfect clarity rating.

Some people actually prefer the bluish tint that a large amount of fluorescence brings to a diamond. Only 1/4 to 1/3 of all diamonds show signs of fluorescence. Of those, 95% are blue. The next most common color of fluorescence appears yellow. Any other color would be possible but exceedingly rare.

Fluorescence is graded on a special scale from None to Very Strong. A diamond with a very strong fluorescence may appear slightly oily but this effect was only found in 2% of the fluorescent diamonds studied by the GIA. (Gemological Institute of America) The fact is that when people were asked to choose between two diamonds without knowing that one had a high fluorescence grade, many of them chose the fluorescent diamond without knowing.

When purchasing diamonds, there are those who look for blue fluorescence because it can make the diamond look clear. A strong yellow fluorescence makes the diamond look dull in UV light. The thing to remember is that the sun is a source of Ultra Violet light and will have an effect on how your fluorescent diamond looks. The NYC Diamond District always test every diamonds and includes its fluorescence grade in the certification. Whether you are looking for fluorescent diamonds or clear, NYC Diamond District is your diamond source.