Graphite is called a two-dimensional metal because it is metallic at intralayer while it is insulator at interlayer. By reducing the interlayer distance, the graphite is expected to become metallic in this direction and then a three-dimensional metal. However, when graphite is pressurized at room temperature, it transforms into a hexagonal diamond, or at high temperature a cubic diamond.
In order to metalize graphite 3-dimensionally before transforming into diamond, a paper which simulates the pressure-induced transformation path of graphite to diamond is reviewed. [1]