Diamond Formation Models

High-Pressure, High-Temperature (HPHT) Method

Diamonds form at depths of 140 to 190 kilometers in the Earth's mantle under high pressure and temperature.

Chemical Vapor Deposition (CVD)

A synthetic process that mimics natural diamond formation, using carbon-containing gases at low pressure.

Subduction Zone

A geochemical model where diamonds form from organic material rich in carbon buried deep in the Earth.

Environmental Conditions for Diamond Formation

Diamonds need to form at depths of 140 to 190 km, under pressures of 5-6 GPa and temperatures of 900°C to 1,300°C.

Inclusions

Tiny minerals trapped within diamonds that provide clues about the diamond's geological environment.

Isotopic Composition

The ratios of carbon isotopes that inform geologists about the source of the carbon in diamonds.

Diamond Age Dating

Radiometric dating techniques used to estimate the age of diamonds based on decay of uranium or thorium.

Depth for Diamond Formation

Diamonds typically form at depths of 140 to 190 kilometers below the Earth's surface.

Carbon Source for Diamonds

Diamonds require a sufficient supply of carbon, often from organic material.

Conditions for Natural Diamond Formation

Pressure around 5-6 GPa and temperatures ranging from 900°C to 1,300°C are favorable for natural diamond formation.