The velocity of compressional waves in rocks to 10 kilobars
. Geophysics, 66(7):p.2199-2224.
The velocity of compressional waves in rock to 10 kilobars
, Part 2.
Zopfi further specifies that at this time the pressure was in excess of 2 kilobars
(more than 2000 atmospheres), and the cleft zone was about 10 km below the surface.
Birch, F.: 1961, The velocity of compressional waves in rocks to 10 kilobars
, Part II.
To meet industry volume demands and emulate the production conditions of diamonds found in nature, artificial synthesis requires the use of high temperatures and pressures--typically around 2,000 K and 60 kilobars
(kbar) using modern diamond presses and nickel catalysts.