What Forms When Carbon Crystallizes At Very High Pressure And Temperature?

What Forms When Carbon Crystallizes At Very High Pressure And Temperature? Carbon may dissolve not only in metals such as Mn, Fe, or Ni but also in molten compounds such as CuCl, AgCl, Cu,S, CdO, or hydroxyl-bearing alumino-silicates at high pressures and temperatures. Diamond may form from Mn, Fe, Ni, etc., but only graphite has