Country: United States
Date: December 2007
How do diamonds form?
A diamond is a transparent gem made of carbon, one of
the earth's most common elements. The formation of
diamonds began very early in the planet Earth's
history, when the condensation of solid matter into a
sphere caused the centre of the planet to become
subjected to incredible extremes of temperatures and
Experiments and the high density of diamonds tell us
that they crystallize at very high pressures. In
nature this means that diamonds are created by
geologic processes at great depth within Earth,
generally more than 150 kilometers down, in a region
beneath the crust known as the mantle.
In the beginning of Earth formation
deposits of carbon element begin to crystallise deep
as diamonds. As the Earth's surface cooled, volcanic
activity forced streams of magna (liquid rock) to the
surface, carrying with it the diamond crystals. Later,
the diamond-bearing rock hardened, encasing the
diamonds in vertical volcanic "pipes".
But not all diamonds are found where they first came
to the surface. Subsequent erosion of the topsoils
over millions of years washed some of the diamonds
into streams and rivers, and sometimes as far away as
the sea. It is highly probable that they were first
discovered in areas such as these, far away from their
Thanks for asking NEWTON!
Mabel (Dr. Mabel Rodrigues)
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Update: June 2012