  We present experimental phase function and degree of linear polarization
curves for seven samples of cometary dust analogues namely: ground pieces of
Allende, DaG521, FRO95002 and FRO99040 meteorites, Mg-rich olivine and
pyroxene, and a sample of organic tholins. The experimental curves have been
obtained at the IAA Cosmic Dust Laboratory at a wavelength of 520 nm covering a
phase angle range from 3{\deg} to 175{\deg}. We also provide values of the
backscattering enhancement (BCE) for our cometary analogue samples. The final
goal of this work is to compare our experimental curves with observational data
of comets and asteroids to better constrain the nature of cometary and
asteroidal dust grains. All measured phase functions present the typical
behavior for \mu m-sized cosmic dust grains. Direct comparison with data
provided by the OSIRIS/Rosetta camera for comet 67P Churyumov-Gerasimenko
reveals significant differences and supports the idea of a coma dominated by
big chunks, larger than one micrometer. The polarization curves are
qualitatively similar to ground-based observations of comets and asteroids. The
position of the inversion polarization angle seems to be dependent on the
composition of the grains.We find opposite dependence of the maximum of the
polarization curve for grains sizes in the Rayleigh-resonance and geometric
optics domains, respectively.
