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Don’t Hate the Fluorescent Diamonds!

Diamonds with fluorescence aren’t all bad, in fact some diamonds need a bit of fluorescence to help its colours. So why do we all hear big brands like Tiffany’s, Harry Winston, Piaget shun this characteristic? 

Know when to hate it and when to love it! Get ready to be surprised!

FLUORESCENCE - the glow you see when an object emits visible light. For a diamond, it is when they emit bluish light (sometimes yellow or orange light) when exposed to ultraviolet (UV) rays such as the Sun.

Fluorescence in Diamonds

Almost 30% of diamonds have some degree of fluorescence, but the GIA considers “Fluorescence” only as an identifying characteristic - it has no grading factor like the other 4Cs. Unlike the typical diamond specifications (Colour, Clarity, Cut & Carat), the price is not adversely affected in a continuous decreasing manner when a diamond show signs of blue light under a fluorescent lamp. In fact, in some cases, it helps increase a diamonds worth!

The Time to Love

Because of the blue tone that a Fluorescent Diamond emit, diamonds with a lower colour grading - with a yellowish tone - will benefit by de-colouring effect. The blue light can mask the undesirable faint yellow in the stone under natural lighting as the colours are complementary in the colour wheel. Hence, a lot of professional jewellers tend to mark 2% higher in prices when blue fluorescent diamonds are found in Colour “I - M” stones. Hey, I get a more affordable diamond that looks Colourless, why not?

The Time to Avoid

Not all diamonds can benefit from Fluorescence though. The opposite holds true for diamonds of better Colour “D - H” and are less desirable in the trade. The body colour of these rocks are too colourless, and cannot offset the degree of Fluorescence you will see under the sun. Although typically diamonds are not adversely affected by fluorescent, depending how strong it is, Fluorescence can be considered a defect and cause a diamond to be sold 15% less.

The Time to Really Hate - and the Vendors who sell them..

First the story: So this happened to my best friend. Sadly I couldn’t have prevented it because she got engaged when I was still an Architect-devotee.

She showed me her proud D Colour VVS1 engagement ring. Nice and big. But I noticed it wasn’t all too clean, like when you fingerprint your iPad screen after applying a nice moisturising hand lotion. It happens, I mean I always get hand lotion on my diamond rings too - I’m rather a skincare maniac. Anyway, so I said to her, Hey I’ll offer to clean your ring for you. I did. It looked the same. What happened??

In really rare cases (only 0.2% of fluorescent pack) the diamonds with Very Strong Fluorescence will create a hazy, milky, oily or cloudy appearance. So screw the VVS1 Clarity quality in its cert, it looks completely like an acrylic plastic. Beware of dishonest vendors that rip you off for not knowing your shit!!

So What to Conclude

Be smart! If you’re not experienced, find an Honest Vendor (like me *wink). Serious though, if you’re paying your month’s salary on something that requires so much technical expertise, you better have an expert you trust guide you to getting the best one. Or if you have a question, ask me here.

Good vendors typically try to stray away from stocking up Medium to Very Strong fluorescent diamonds in the first place, so you really have nothing to worry about. Oooh, maybe that would be a good hint to weed out a bad store if you see one lying around. Maybe.

But do remember that many trade professionals sell Faint Fluorescence as the technique to decolour faint yellow stones do really increase its worth AND it is beneficial to the end-user too. 

All in all, always compare loose stones on a white paper. Compare with good master stones to see if you find the one you like acceptable. Then you’ll know if the Fluorescent factor really matters to you.

Who Am I?

I am Janet Tam, part of the new movement of Jewellers that believe in human connection and collaboration. I love to meet people to create ideas and develop inspiration.

Registered and still practising as a Professional Architect in Hong Kong, I was brought up in a Jeweller’s family - counting diamonds, artistry and design has always been in my blood.

Images Courtesy of Pinterest & GIA Gemological Institute of America Inc.

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