The predominant spatial control on sulfide orebodies at two significant base metal deposits, Kipushi (Democratic Republic of Congo) and Gayna River (Canada), is the architecture of Neoproterozoic carbonate lithofacies. At the Gayna River Zn camp, surface and subsurface mineralization is limited to the peripheries of giant pinnacle reefs of an unusual type hitherto considered unique. At the past-producing Kipushi Cu-Zn deposit, orebodies are associated with a lithologic break, until now interpreted as a fault but here reinterpreted as the steep depositional margin of a carbonate buildup similar to those at Gayna River. The zone of compositional and rheological contrast that generated where reef-flanking and overlying fine-grained terrigenous strata contact the Kipushi carbonate buildup appears to have focused later metalliferous fluid migration. This reinterpretation of two iconic deposits highlights the importance of considering sedimentary-stratigraphic controls on carbonate-hosted base metal deposits in mineral exploration programs.