Gold: a useful tracer in sub-Sahelian laterites

Sequential and connected lateritic sequences from the Tertiary to present day can be observed in sub-Sahelian conditions in northern Burkina Faso (Michel, 1973; Grandin, 1 975 ). Here, complex iron auriferous crust systems have developed on the stable West African Craton from Proterozoic auriferous greenstone belts and volcanic tuff. In order to distinguish between chemical and physical processes which have led to the development of the lateritic systems, we propose to use visible gold particles as pathfinders. In this paper, we focused on the lowland lateritic system (profile of pit P4) located downslope to the middle land lateritic system, where gold is associated with hydrothermally altered quartz veins and pebbles (Fig. 1 ) .