  A Markov process is constructed to numerically study the phase separation in
the 6-vertex model with domain wall boundary conditions. It is a random walk on
the graph where vertices are states and edges are elementary moves. It
converges to the Gibbs measure of the 6-vertex model. Our results show clearly
that a droplet of "c" vertices is created when Boltzamnn weights are in the
antisegnetoelectric region. The droplet is a diamond-like shaped curve with
four cusps.
