Diamond Crystallization from an Antimony–Carbon System under High Pressure and Temperature

Abstract

We report the results of an experimental study on diamond crystallization in the Sb–C system under HPHT conditions. The experiments were run at pressures of 6.3 and 7.5 GPa in the temperature range of 1500–1800 °C for 1 to 40 h. Diamond crystallization via spontaneous nucleation and growth on the seed crystals has been established. It is shown that the kinetic factor plays a crucial role in diamond crystallization in the Sb–C system. For run duration of 40 h the minimal P–T parameters of diamond growth on the seed crystals are found to be 6.3 GPa and 1500 °C, while the minimal parameters for spontaneous nucleation are 7.5 GPa and 1600 °C.