  The liquid-gas transition of an electroneutral mixture of oppositely charged
colloids, studied by Monte Carlo simulations, is found in the low temperature
-- low density region. The critical temperature shows a non-monotonous behavior
as a function of the interaction range, $\kappa^{-1}$, with a maximum at
$\kappa \sigma \approx 10$, implying an island of coexistence in the
$\kappa$-$\rho$ plane. The system is arranged in such a way that each particle
is surrounded by shells of particles with alternating charge. In contrast with
the electrolyte primitive model, both neutral and charged clusters are obtained
in the vapor phase
