How does a diamond get its blue color?

How does a diamond get its blue color?

Blue diamonds are extremely rare and have an almost mythical status. It is the Holy Grail for every woman and jeweller. But what gets this diamond to its coveted blue colour?

An authentic diamond consists of carbon and is usually colourless. When a colour is created, it comes from other elements or from an error in the structure of the diamond.

The difference between colourless and blue diamonds

Blue diamonds get their colour from the chemical elements and semi-metal boron that in the course of time became intertwined in the crystal structure of the diamond.

Colourless diamonds are clear because the carbon atoms do not have moving free electrons. Carbon atoms have four electrons, with which they make connections to four adjacent atoms. This ensures that light gets a free passage.

Boron has only three ‘connections electrons’. This means that for each boron atom, one of its four carbon neighbors has an unused electron. This absorbs red light, which results in a blue color. Only a couple of boron atoms can be enough to colour a diamond blue.

Red diamonds: even rarer than blue diamonds

Despite his status, the blue diamond is not even the rarest stone on the planet. That honour is reserved for pink and especially red diamonds. They get their colour by the heat that got released when they were forcibly pushed out of the earth’s crust. Because of the enormous pressure, the diamond structure changed, whereby the electrons absorb more blue light and produce a red colour.

Worldwide there are only 200,000 diamonds that even exhibit just a little bit blue. Deep blue ones are almost impossible to find. In recent years, there have been developed a number of techniques in order to affect the colour. But even these treated diamonds are very rare.

Are you unfortunately not a millionaire? But do you want to surprise your loved one with an authentic diamond jewel? Then you can take a look in the phenomenal jewellery range of BAUNAT, the most favourable online jeweller in Belgium! You will certainly find there a wonderful jewel for any occasion. From engagement rings and earrings to bracelets and necklaces.

Author: Claudine Kuypers

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