  We report on a population of absorption systems selected by the presence of
very weak Mg II doublets. A sub-population of these systems are iron enriched
and have near solar metallicities. This would indicated advanced stages (i.e.
few Gyr) of in situ star formation within the absorbing structures. From
photoionization modeling, we infer low ionization fractions of f(HI/H)~0.01,
and gas densities of ~0.1 cm^-3. Since the maximum HI column densities are
\~10^17 cm^-2, the inferred cloud sizes are ~10 pc. From their redshift number
densities, this implies that their co-moving spatial density outnumbers normal
bright galaxies by a factor of a few million.
