Quasar metal absorption lines provide a proximate means of studying star formation activity shortly after reionization. I present results from a new search for C IV at z~6 in the high-resolution infrared spectra of four high-z QSOs. These are the first data with enough path length and sensitivity to place strong constraints on the evolution of highly-ionized, metal enriched absorbers at these redshifts. Early indications are that the number density of C IV systems is at least a factor of two lower at z~6 than at z~3. I will discuss the implications for high-z star formation, IGM enrichment, and reionization.
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