  General Majorana neutrino mass matrix is complex symmetric and for three
generations of neutrinos it contains 12 real parameters. We diagonalize this
general neutrino mass matrix and express the three neutrino masses, three
mixing angles, one Dirac CP phase and two Majorana phases (removing three
unphysical phases) in terms of the neutrino mass matrix elements. We apply the
results in the context of a neutrino mass matrix derived from a broken cyclic
symmetry invoking type-I seesaw mechanism. Phenomenological study of the above
mass matrix allows enough parameter space to satisfy the neutrino oscillation
data with only 10% breaking of this symmetry. In this model only normal mass
hierarchy is allowed. In addition, the Dirac CP phase and the Majorana phases
are numerically estimated. $\Sigma m_i$ and $|m_{\nu_{ee}}|$ are also
calculated.
