Diamond

Hardness: 10 (Mohs scale), Color: Colorless (in this specimen), Luster: Adamantine, Crystal Structure: Cubic, Cleavage: Perfect in four directions, Specific Gravity: 3.5-3.53

Formed under extreme pressure and high temperatures deep within the Earth's mantle, typically at depths of 140 to 190 kilometers, and brought to the surface by kimberlite eruptions.

Primarily used in high-end jewelry and industrial applications such as cutting, grinding, and drilling due to its unparalleled hardness.

The name comes from the Greek 'adamas', meaning invincible. They are over a billion years old. The Cullinan Diamond is the largest gem-quality rough diamond ever found.

Identify in the field by its extreme hardness (cannot be scratched by any other material) and high refractive index. Commonly found in kimberlite pipes or alluvial deposits in South Africa, Russia, and Canada.