  In preparation for the release of the astrometric orbits of Gaia, Shahaf et
al. (2019) proposed a triage technique to identify astrometric binaries with
compact companions based on their astrometric semi-major axis, parallax, and
primary mass. The technique requires the knowledge of the appropriate
mass-luminosity relation to rule out single or close-binary main-sequence
companions. The recent publication of the Gaia DR3 astrometric orbits used a
schematic version of this approach, identifying 735 astrometric binaries that
might have compact companions. In this communication, we return to the triage
of the DR3 astrometric binaries with more careful analysis, estimating the
probability for its astrometric secondary to be a compact object or a
main-sequence close binary. We compile a sample of 177 systems with
highly-probable non-luminous massive companions, which is smaller but cleaner
than the sample reported in Gaia DR3. The new sample includes 8 candidates to
be black-hole systems with compact-object masses larger than 2.4 $M_\odot$. The
orbital-eccentricity$-$secondary-mass diagram of the other 169 systems suggests
a tentative separation between the white-dwarf and the neutron-star binaries.
Most white-dwarf binaries are characterized by small eccentricities of about
0.1 and masses of 0.6 $M_\odot$, while the neutron star binaries display
typical eccentricities of 0.4 and masses of 1.3 $M_\odot$.
