Vitreous or Glassy carbon is a form of pure carbon produced by the thermal decomposition of a three-dimensionally crosslinked polymer. It has a high flexural strength. The zero open porosity gives a low permeability to gases. Glassy carbon has excellent resistance to a wide range of aggressive chemical enviroments and can, therefore, be used as an alternative material to precious metals for laboratory equipment and, for example, for electrodes in polarography.