  The relevance of galaxies of different luminosity and mass for the chemical
enrichment of the intracluster medium (ICM) is analysed. For this purpose, I
adopt the composite luminosity function of cluster galaxies from Trentham
(1998), which exhibits a significant rise at the very faint end. The model -
adopting a universal Salpeter IMF - is calibrated on reproducing the
M_Fe/L_tot, M_Fe/M_*, and alpha/Fe ratios observed in clusters. Although the
contribution to total luminosity and ICM metals peaks around L* galaxies (M*
approx -20), faint objects with M_B>-18 still provide at least 30 per cent of
the metals present in the ICM. In consistency with the solar alpha/Fe ratios
determined by {ASCA}, the model predicts that 60 per cent of the ICM iron comes
from Type Ia supernovae. The predicted slope of the relation between
intracluster gas mass and cluster luminosity emerges shallower than the
observed one, indicating that the fraction of primordial gas increases with
cluster richness.
