Diamond in Kimberlite

Physical Properties

Hardness: 10 (diamond), 6 (matrix); Color: brownish-grey matrix with clear inclusion; Luster: Adamantine (diamond), Dull/Earthly (matrix); Crystal structure: Isometric (diamond)

Formation & Geological History

Formed in the Earth's upper mantle at extreme pressure and temperature, transported to the surface via volcanic pipes (kimberlite eruptions) originating from depths of over 150 km.

Uses & Applications

Primary source of industrial and gemstone-grade diamonds; highly valued by geological collectors as a 'frozen' piece of the deep mantle.

Geological Facts

Kimberlite is named after the town of Kimberley in South Africa. Diamonds are the only gemstones made of a single element (carbon) and are the hardest natural substance on Earth.

Field Identification & Locations

Identify by searching for ultra-mafic rocks with heavy minerals like garnets and olivine; commonly found in cratons in South Africa, Russia, Canada, and Australia.

Identified on: 5/19/2026

Mode: Standard