How are Natural Diamonds formed?

How are Natural Diamonds formed?

 Contrary to popular belief, coal has rarely, if ever played a role in the formation of diamonds.  3 billion years ago deep within the Earth’s crust under conditions of intense heat and pressure that cause carbon atoms to crystallize forming diamonds.  The formation of natural diamonds requires very high temperatures and pressures, and there are 4 known ways this can happen in nature.

As Seen on The Knot