Blue Diamond Gems Forms In the Depth of Earth's Mantle

This is a new research that blue diamond gems are formed into the lower mantle of the earth which is deeper reaching almost 660-kilometre (410 miles). Here is the place where boron is scarce. Researches point out that blue diamond inclusions point out the formation happens almost deep -subducted oceanic plates.




Blue diamonds is one of the most precious and rare gemstones. More than other diamonds. Comparatively other diamonds, they are formed 4 deeper. Researchers have thought that it may have element boron which is the cause of blue. This new research has been featured on a famous international scientific journal " Nature".

Dr. Evan Smith, who is the lead author of the Nature article (GIA (Gemological Institute of America) research scientist) and his colleagues worked on this findings. Evan is a geologist in GIA, based in New York. GIA has studied many million of diamonds from all over the world.

Evan said " “Blue diamonds like the famous Hope diamond have intrigued scientists for decades, but the rarity and high value of these gems and their near lack of mineral inclusions have been major hurdles to research,”

[caption id="attachment_423" align="aligncenter" width="535"]Learn also about Rare Grandidierite Gemstones Learn also about Rare Grandidierite Gemstones[/caption]

“The opportunity to study these rare diamonds at GIA gave us insight to their incredible origin.”

Blue diamonds are also called IIb diamond.  Boron is itself a rare element which is not so commonly found on earth.  Interesting thing is that blue diamonds are formed very deep inside the earth like 660 kilometres which are more below the mantle's lower and upper layers. Usually, diamonds are formed above the boundary level.



[caption id="attachment_1915" align="alignleft" width="297"] 14.62 carat rare fancy blue diamond  "Oppenheimer Blue" 
(Photo credit should read FABRICE COFFRINI/AFP/Getty Images)[/caption]

Their structure and chemical recipe point to an origin more than 660 kilometers (410 miles) deep. That’s below the boundary between the mantle’s upper and lower layers. All diamonds are within Earth ’s above the boundary layer. The other interesting thing is that blue diamonds are normally flawless. The inclusion is usually considered a flaw inside the diamond. Small quantities of boron are affecting the blue diamond. Boron is a chemical found in Earth's crust. Although diamonds are formed in the mantle of Earth - below the crust. Here is where diamonds find enough pressure and temperature to get formation or hardness in the stone. Research shows that blue diamond is formed deep inside oceanic plates.


Source: GIA -


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