Diamond

Diamond

Miba Mine, Mbuji Mayi, Kasaï-Oriental, Democratic Republic of Congo

Diamond

Kimberley, Francis Baard District, Northern Cape Province, South Africa

Diamond

Kimberley, Francis Baard District, Northern Cape Province, South Africa

Formula:

C

System:

Isometric

Colour:

Colourless, yellowish to ...

Lustre:

Adamantine, Greasy

Hardness:

10

Name:

From Greek "adamas", 'invincible'. First known use by Manlius (A.D. 16) and Pliny (A.D. 100).

Polymorph of:

Chaoite, Graphite, Lonsdaleite

Diamond is the hardest natural substance known. It is formed deep in the mantle, and is only brought to the surface via kimberlite pipes, lamprophyres, eclogites and other rocks that originate deep within the mantle. It is also found in alluvial deposits, along with quartz, corundum, zircon and other minerals, derived from such rocks, and in certain meteorites.

The formation processes of the variety carbonado are unclear.