In principle, an internally heated pressure vessel (IHPV) consists of a thick-walled pressure vessel sealed by closure plugs at the ends. In addition, there is a pressure inlet/outlet as well as several electrical leads into the vessel for power supply to and temperature control of the internal furnace. The equipment is particularly designed for experimental studies at medium to high temperatures (currently up to 1250 °C) and pressures up to 10 kbar. This P-T range is inaccessible by …