Diamond in Kimberlite

Physical Properties

Kimberlite: Hardness 4-6, dull/earthy luster, dark green to gray color. Diamond crystal: Hardness 10, adamantine luster, isometric crystal system.

Formation & Geological History

Formed in the Earth's mantle at high pressure and temperature (150-200 km deep) and brought to the surface through explosive volcanic pipes called kimberlite pipes.

Uses & Applications

Primary source for commercial diamond mining (industrial and jewelry grades). Specimens are highly valued by geological collectors.

Geological Facts

Kimberlite is named after Kimberley, South Africa, where the first significant diamond pipes were discovered. Not all kimberlites contain diamonds; only about 1% are economically viable.

Field Identification & Locations

Identify in the field by looking for 'Blue Ground' (weathered kimberlite), presence of indicator minerals like pyrope garnet, chrome diopside, and ilmenite.

Identified on: 4/25/2026

Mode: Standard