  As needed for the construction of rank $n$ continuous frames on a right
quaternionic Hilbert space the so-called S-spectrum of a right quaternionic
operator is studied. Using the S-spectrum, as for the case of complex Hilbert
spaces, along the lines of the arguments of {\em Ann.Phys.}, {\bf 222} (1993),
1-37., various classes of rank $n$ continuous frames and their equivalencies on
a right quaternionic Hilbert space are presented.
