Diamond Trivia

Round cut diamonds have 58 facets.

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Diamond Fluorescence

If you’re searching for the perfect diamond, then please contact me, and let me know your budget and what you’re looking for. I’ll sift through hundreds of thousands of diamonds and recommend the perfect stone for you and your budget. Unlike the other sites, I’m not looking to sell you anything – my advice is objective and in your best interest. You have nothing to lose and a larger diamond or saving hundreds of dollars to gain.


Bottom Line Recommendation:  If your diamond is H, I, or J color, then look for a diamond with Medium Blue fluorescence for an added bonus – it can make your stone look slightly whiter.  If not, your stone will still look great without it.  If you are buying a diamond with a G or higher color, then find a diamond with either no fluorescence or faint fluorescence.  According to James Allen’s page on Diamond Color, “Strong blue fluorescence can make a yellow colored diamond appear more white, but in rare cases can cause a stone to appear milky or oily.”

Diamond Fluorescence refers to how a diamond responds when subjected to ultra-violet light.  UV light is what makes your whites look whiter, your teeth bright white, and your black-light posters glow.  Some diamonds, when they are exposed to UV light, glow different colors.  I’m not going to even try to explain why this is.  If you’re interested, google diamond fluorescence, and I’m sure you’ll find more than enough information about the science behind the glow.  99% of the time, the glow is blue in color, but on rare occasions, the diamonds can glow white, yellow, green, or even red in color.
diamond_fluorescenceThe story, however, doesn’t end here.  After all, if the diamond only glows when exposed to UV light, it should naturally only matter if you are someone who spends their days in dark rooms with black-light lamps (dance clubs, rides at Disney World, etc).  But the fact is, most diamonds exhibiting Strong Blue Fluorescence appear slightly to severly hazy in regular light.
If you’ve done your homework and googled diamond fluorescence, then you might have read about a certain GIA study claiming that even strong blue fluorescence is almost always entirely imperceptible to the average diamond consumer.

I can tell you with absolute certainty, that their research is bunk.  I have seen tens, if not hundreds, of thousands of diamonds in my career and I can tell you without question the following:

  • Strong/Very Strong Blue Fluorescent diamonds usually appear hazy
  • Medium Blue Fluorescent diamonds rarely appear hazy
  • Slight/Faint Blue Fluorescent diamonds never appear hazy

The study, though, does make one claim that is correct.  Fluorescence will usually improve the appearance of color in the diamond.  So as I suggested in my bottom line recommendation above, if you are buying a diamond with a color H or lower, seek out a diamond with Medium Blue Fluorescence.  I am hesitant to suggest looking for a diamond with Strong Blue Fluorescence, since even lower colors can occasionally look milky and hazy when they have Strong Blue Fluorescence.  I am also hesitant to suggest Medium Blue Fluorescence when purchasing a diamond with a very high color (G or better), since on rare occasions even a Medium Blue Fluorescent diamond can exhibit milkiness or haziness when the color is exceptionally high.  If, of course, you are buying a diamond in person and not online, then it’s in your best interest to specifically ask for a diamond with Strong Blue Fluorescence.  It will be cheaper and since you are there in person, you can see for  yourself whether or not the diamond exhibits haziness or milkiness.

Despite the savings you might gain by buying a Strong Blue Fluorescent diamond, it will certainly still be cheaper for you to buy your diamond online and purchase either a Medium or lower fluorescence.  Unfortunately, however, even James Allen with their advanced photography, cannot show you how the diamond will look face-up in direct sunlight.

If you have any questions, please post them in the comments below.  I will usually respond within 24 hours.

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