Q. What are Natural Diamonds?

A. The name Diamond is derived from the Greek word Adamos which means unalterable, unbreakable and untamed.

Diamonds are the hardest substances on Earth. They have the highest thermal conductivity, the highest electrical resistance and they are the most chemically inert natural substances on earth.


Q. How are Natural Diamonds formed?

A. A diamond is pure carbon and is formed inside the Earth’s mantle about 150 – 250 kms below the Earth’s surface and Diamonds were carried to the earth’s surface through volcanic eruptions.

Most diamonds are 1 billion to 3.5 billion years old so they could even pre date the dinosaurs.

Extreme temperatures around 1000 degrees Celsius and high pressure below the Earth’s surface resulted in modifying graphite – a crystalline carbon on the atomic level which restructured it’s molecular composition thereby resulting in a diamond.

Q. The History of Natural Diamonds!

A. Historically diamonds were originally found in sediments of lose rocks in India. Diamond extraction from mining only started in the late 1800’s after the discovery of a diamond mine in South Africa. They are almost always found in the oldest parts of the stable core of the continent, which typically ages 2.5 billion years or more so basically really old parts of the world.

Accordingly roughly 50% of the diamonds originate from Central and Southern Africa. The other significant sources of diamonds have been discovered in Canada, India, Russia, Brazil and Australia.

Q. What makes natural diamonds rare?

A. The average yield of a diamond mine is 1 part diamond to 1 million part host rock. Most of the diamond formation took place in the first couple billion years of Earth’s history. The younger diamond rocks discovered like Kimberlite is itself hundreds of millions of years old.

Diamonds are dated looking at the inclusions of other minerals in it, which can be radioactively dated as diamonds itself can’t be dated. Therefore it could be rightly said that Diamonds are very rare.

Posted in: Gemschool by PJS
Akshay Chawla
Akshay Chawla, a postgraduate from the University of Warwick and a Graduate Gemologist from the Gemological Institute of America.