Covering much of what we now call the Maghreb of northern Africa, masses of these shelled microorganisms inhabited that exotic marine environment,[2] depositing their tiny crusty carcasses on the bottom as they died.

Over eons, tectonic forces laterally compressed southern regions of this sedimentary basement, thrusting the seafloor upward along contorted faults and displacing the sea northward to its present shoreline.

Earliest references in literature indicate the countryside adjacent to Djebel Ressas was possibly the location of a famous military engagement, fought and won decisively by the empire of Carthage against rebel mercenaries and other local enemies, late in the 2nd century BC.

In Tunisian Arabic, the name Djebel Ressas literally means ‘mountain of lead’, a reference to the ore that was mined there, perhaps from Roman times until the late 19th or early 20th century.

Materials from this site are used to produce cement and stone matter for meeting the demands of Tunisia's rapidly expanding road systems and building infrastructure.