Skip to main content


In The KnowStyle & Trends

Blue Diamonds

17th September 2018August 17th, 2022No Comments

Blue diamonds have been in the news recently, as scientists have found that mined blue diamonds are formed up to four times deeper in the earth’s crust than their clear cousins.  Scientists from the Carnegie Institute of Science were able to study 46 blue diamonds, to try to establish where they are formed.  Their results show that they are formed deeper in the earth’s mantle than previously thought, between 250 and 410 miles below the earth’s surface.

The scientists examined tiny specks within the diamonds, impurities known as inclusions, using spectroscopy to determine their chemical make-up, establishing that the inclusions were fragments of rocks from the lower mantle of the earth, further down than any other gems.  Understandably, they weren’t allowed to cut open the diamonds, as blue ones are far rarer than regular white diamonds!

Mined blue diamonds gain their blue colour from boron, an element found at the earth’s surface, and in underwater mineral deposits, but until this piece of research, no-one had been able to establish precisely how  this occurs.  Now scientist believe that the surface boron was forced deep into the earth by tectonic plate movements, pushing it into the same areas in which the diamonds were being formed.

In the world of mined diamonds, blue diamonds account for 0.02% of the gems found.  They are very desirable and highly sought-after, so you are unlikely to be able to purchase one unless you have very deep pockets indeed!

Blue Diamonds - What's So Special? | Ethica Diamonds | Cornwall | UK

We introduce measured amounts of boron into the chamber when the carbon is being formed into the diamond layers, and it is then trapped in the lattice structure.  This means that when you look at the diamond, blue light reflects back.

We are hoping to provide blue Lab Grown Diamonds in the near future.  For now though, we can source blue lab-grown sapphires, which are the next best thing.

Here is an example of blue lab-grown sapphires made into a bespoke ring, for you to take as inspiration – enjoy!Lab grown sapphires and diamonds

Don’t Miss Out!

Be the first to know all about our offers
and news by signing up to our newsletter

"*" indicates required fields

This field is for validation purposes and should be left unchanged.

Don’t worry, we won’t send you any junk! Opt out at anytime.
View our Privacy Policy