Carbon is a truly remarkable element which can exist as one of several allotropes. It is found abundantly in nature as coal or as natural graphite, and much less abundantly as diamond. Moreover, it is readily obtained from the pyrolysis of hydrocarbons such as resins and pitches, and can be deposited from the vapor phase by cracking hydrocarbon rich gases. In its various allotropic forms carbon has quite remarkable properties. Diamond possesses the highest thermal conductivity known to man and is prized as a gem stone. Both of these attributes result from the high degree of crystal perfection and bond strength in the diamond lattice. Graphite possesses extreme anisotropy in the bond energies of its crystal lattice, resulting in highly anisotropic physical properties. The most recently discovered allotrope of carbon, C60 or Buckminsterfullerene, has been the subject of extensive research, as have the related carbon nanotubes and nanostructures.