A chemical vapor deposited diamond film was grown on a silicon substrate by the plasma arcjet method. The deposited film was circular and appeared to be radially zoned under visual examination. A secondary electron microscope was used to examine the surface morphology and microfocus Raman spectroscopy was used to examine the radial compositional variation of the film. Raman spectroscopy shows that the composition of the diamond film changed markedly in the space of hundreds of microns. Changes in the Raman spectra can be correlated with variations in morphology of the diamond film.