  We report the discovery of a new carbon rich white dwarf that was identified
during a proper motion survey for cool white dwarfs based on photographic
material used for the construction of the Guide Star Catalog II. Its large
proper motion (0.48 arcsec/yr) and faint apparent magnitude (V = 18.7) suggest
a nearby object of low luminosity. A low-resolution spectrum taken with the
William Herschel Telescope clearly shows strong C2 Deslandres-d'Azambuja and
Swan bands, which identify the star as a DQ white dwarf. The strength of the
Deslandres-d'Azambuja bands and the depression of the continuum in the
Swan-band region are signs of enhanced carbon abundance for the given Teff.
Comparison of our spectrophotometric data to published synthetic spectra
suggests 6000 K < Teff < 8000 K although further analysis with specialized
synthetic models appear necessary to derive both Teff and chemical composition.
Finally, the range of spatial velocity estimated for this object makes it a
likely member of the halo or thick disk population.
