gemstone
Diamond
Carbon (C)
Hardness: 10 (Mohs scale), Color: Colorless to faint yellow/brown, Luster: Adamantine, Crystal Structure: Cubic, Cleavage: Octahedral, Specific Gravity: 3.51
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Physical properties
Hardness: 10 (Mohs scale), Color: Colorless to faint yellow/brown, Luster: Adamantine, Crystal Structure: Cubic, Cleavage: Octahedral, Specific Gravity: 3.51
Formation & geological history
Formed under extreme pressure and temperature in the Earth's mantle (100 miles deep) over 1 to 3.3 billion years ago, then transported to the surface by kimberlite eruptions.
Uses & applications
Jewelry (engagement rings, etc.), industrial abrasives, cutting tools, and high-tech heat sinks.
Geological facts
Diamond is the hardest natural substance known to man and carries the highest thermal conductivity of any natural material.
Field identification & locations
Identified by its high refractive index (sparkle), extreme hardness (scratches all other minerals), and high thermal conductivity. Commonly mined in Botswana, Russia, Canada, and South Africa.
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