  The metal--insulator phase transition is considered on the basis of
Ginzburg-Landau type equations with two different order parameters. An
inclusion of magnetic field in this picture is an important step for
understanding of behavior of the metal--insulator phase transition kinetics.
The magnetic field leads to various singularities of the surface tension and
results in drastic variations of the phase transition kinetics. The strongest
singularity is due to Landau diamagnetism and determines anomalous features of
MI transition kinetics. This singularity supports the well known experimental
fact that almost all semimetals behave like diamagnetic materials.
