  This is the second paper in a series of three in which we present an
exhaustive inventory of the 49 solid state emission bands observed in a sample
of 17 oxygen-rich dust shells surrounding evolved stars. Most of these emission
bands are concentrated in well defined spectral regions (called complexes). We
define 7 of these complexes; the 10, 18, 23, 28, 33, 40 and 60 micron complex.
We derive average properties of the individual bands. Comparison with
laboratory data suggests that both olivines (Mg(2x)Fe(2-2x)SiO(4)) and
pyroxenes (Mg(x)Fe(1-x)SiO(3)) are present, with x close to 1, i.e. the
minerals are very Mg-rich and Fe-poor. This composition is similar to that seen
in disks surrounding young stars and in the solar system comet Hale-Bopp. A
significant fraction of the emission bands cannot be identified with either
olivines or pyroxenes. Possible other materials that may be the carriers of
these unidentified bands are briefly discussed. There is a natural division
into objects that show a disk-like geometry (strong crystalline silicate
bands), and objects whose dust shell is characteristic of an outflow (weak
crystalline silicate bands). In particular, stars with the 33.5 micron olivine
band stronger than about 20 percent over continuum are invariably disk sources.
Likewise, the 60 micron region is dominated by crystalline silicates in the
disk sources, while it is dominated by crystalline H(2)O ice in the outflow
sources. We show that the disk and outflow sources have significant differences
in the shape of the emission bands. This difference must be related to the
composition or grain shapes of the dust particles. The incredible richness of
the crystalline silicate spectra observed by ISO allows detailed studies of the
mineralogy of these dust shells, and is the origin and history of the dust.
