Diamond-like carbon (DLC) is a term which covers many new forms of carbon which have both graphitic and diamond like characteristics.  The two images to the left show a couple of extreme cases; one being crystalline the other amorphous and smooth, each are 5x3 micrometers in size.  The top image is made by a chemical vapor deposition technique; the image is from a scanning electron microscope (SEM).  The lower image is made by PLD from a pyrolitic graphite target; the image is from an atomic force microscope (AFM).  DLC has many possible material properties as it becomes more diamond like and crystalline.  Its density is between graphite and diamond (2.2-3.5 grams/cubic centimeter).  The optical properties are diamond like in index of refraction but a high extinction coefficient makes them dark.  DLC is being used in the semiconductor industry and as a wear resistant coating.