It is shown numerically that strange matter rings permit a continuous
transition to the extreme Kerr black hole. The multipoles as defined by Geroch
and Hansen are studied and suggest a universal behaviour for bodies approaching
the extreme Kerr solution parametrically. The appearance of a `throat region',
a distinctive feature of the extreme Kerr spacetime, is observed. With regard
to stability, we verify for a large class of rings, that a particle sitting on
the surface of the ring never has enough energy to escape to infinity along a
geodesic.Comment: 16 pages, 11 figures, v3: minor changes so as to coincide with
published versio
