Microscopic vacuum structure in a pure QCD.

We propose a class of stationary color magnetic solutions in a pure quantum chromodynamics (QCD) which are stable under gluon quantum fluctuations. This resolves a long-standing problem of microscopic description of a stable non-trivial vacuum in a pure QCD. The solutions represent fixed points in a full space of gauge fields under Weyl group transformations. An important feature of the solutions is the phenomenon of Weyl invariant Abelian projection and Abelian dominance in the vacuum structure. As an application of our approach we consider an effective Lagrangian of pure Abelian glueballs in the presence of vacuum gluon condensate.