Specimens of high density graphite, anisotropic (2.2 g·cm~(-3)) and isotropic (2.0 g·cm~(-3)), were heated over several microseconds by an electrical pulse in thick-walled sapphire tubes. The transition of the liquid carbon's electrical resistivity from semimetal to metal-like characteristics was obtained at a high input energy (25-5 MJ·kg~(-1)). A comparison with similar effects for metals is discussed. Graphite's melting temperature of 4800 K is used for the high temperatures calculations. Temperatures higher than the melting point were roughly estimated, using previously measured Cv value (heat capacity under constant volume). The estimated temperature at the input energy (75 MJ·kg~(-1)) for liquid carbon (density 1.76 g·cm~(-3)) is ～23,000 K, with a correspondent measured electrical resistivity of 3,000 μΩ cm. The estimated temperature reached is ～35,000 K (electrical resistivity of ～1600 μΩ cm) for the liquid carbon (density 1.38 g·cm~(-3)) at the maximum input energy (110 MJ·kg~(-1)).
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