1.23 Carat D SI1 Round Diamond

High Pressure-High Temperature (HPHT) diamond growth occurs within large pressure cookers called cubic presses, which can exert more than 70 metrics tons. To grow a diamond in a cubic press, small diamond seeds are carefully placed into the bottom of a growth cell. A layer of additional carbon, in form of graphite, is then delicately placed on top of the diamond seeds. The growth cell is then placed into the center of the cubic press and heated to 1 500 degrees C while being subjected to 1 million psi of pressure, which is approximately 70 000 times the pressure at sea level! At that temperature and pressure, the graphite in the growth cell is melted into a liquid and then very carefully cooled into our favorite form of carbon, a diamond.