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 ( { H~ { } I / H _ { tot } } ) \simeq 0.01 , and gas densities of \sim 0.1 cm ^ { -3 } .
Since the maximum H I column densities are \sim 10 ^ { 17 } cm ^ { -2 } , the inferred cloud sizes are \sim 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 .