Pozzolanic and hydraulic activity of bauxite for binder … The Ma'aden's exploration area covers approximately 6000 km 2, centered in the town of Az Zabirah (northwest of Riyadh), with elevations of 535–600 m above sea level [2,3] indicate that the bauxite layers have a similar mineralogy, and that their main textures are microooliths, ooliths and pisoliths …