Blue Diamond Expert Tips

05 March 2019

Natural blue diamonds are incredibly rare. So rare in fact, that most jewellers will go their entire careers without ever seeing one. Moreover, the Natural Color Diamond Association states that only one natural blue diamond can be found for every 100 Picasso paintings up for auction.

What gives blue diamonds their unique colour?

Blue diamonds are classified as type IIb, making up about 0.1 percent of the world’s diamonds. Rather than containing clusters of nitrogen as seen in the majority of diamonds, blue diamonds contain trace elements of boron. Boron causes the gem to emit a light blue or grey colour. Due to its trace elements, if you expose the blue diamond to UV light, it will display a blue glow exclusive to the blue diamond. The only exception is the infamous Hope Diamond, which generates a red glow instead of blue; a trait that still remains minutes after a UV light is being removed.

The blue diamond expert tips

An authentic blue diamond has never been treated with chemicals or heat in order to receive its colour. It is important to verify that the stone is natural by looking at its origin in the GIA certificate provided by your jeweller.

Gemstone manufacturers treat unnatural blue diamonds with radiation to infuse blue into the stone. Irradiated blue diamonds are a bright shade of blue, often with a hint of green. These diamonds have a stunning appearance, but shoppers must be wary of synthetic copies if they desire the real thing.

shirley temple's blue diamond ring
Shirley Temple’s father presented her with this iconic blue diamond ring when she was 12 and about to star in the 1940 film The Blue Bird. Temple kept the 9.54-carat, fancy deep blue, cushion-cut diamond ring until she died in 2014. The ring design itself is stunning; with a split shank band set with baguette-cut diamonds.

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