  In this paper, we introduce a partial order on rings with involution, which
is a generalization of the partial order on the set of projections in a Rickart
*-ring. We prove that a *-ring with the natural partial order form a
sectionally semi-complemented poset. It is proved that every interval [0,x]
forms an orthomodular lattice in case of abelian Rickart *-rings. The concepts
of generalized comparability (GC) and partial comparability (PC) are extended
to involve all the elements of a *-ring. Further, it is proved that these
concepts are equivalent in finite abelian Rickart *-rings.
