Fig. 75: Images showing the melting of iron at 2 GPa. (a) at 1500°C the very grainy solid sample, just before melting, gives rise to many diffraction spots. (b) after melting at 1800°C, the spots are replaced by diffuse diffraction rings corresponding to the liquid.

The sharp diffraction peak present in both images is due to the pressure transmitter and calibrant, hexagonal boron nitride.