Facts & Figures
The Earth
From deep inside the earth — born in cooling magma at 1,300°C and 70,000 atmospheres, then carried up through ancient volcanic pipes.
According to the best-known theory, diamonds form in cooling liquid magma at an initial temperature of about 1,300°C and a pressure near 70,000 atmospheres — conditions found only 130 to 200 kilometres below the surface, beneath active volcanoes.
They reach us only by accident of violence. Carried up through volcanic chimneys the miners call pipes — between 100 million and 1.2 billion years old — diamonds survive the journey only if the eruption is fast enough to cool them before they turn to graphite. Such eruptions no longer happen today. Every diamond, then, is a survivor of an earth that no longer exists.
