Mineral sands

Abstract

Mineral sand deposits fall into three main deposit styles, palaeo marine placers, aeolian (dunal) sands and alluvial deposits. Two types are included into the current review. These are palaeo marine placers, Fort Dauphin located in Madagascar and Corridor Sands in Mozambique, and Richards Bay deposit in South Africa, which is aeolian type mineral sands deposit. The main challenges in evaluating of the mineral sands deposits are as follows: • mineral sands deposits comprise non-consolidated to semi-consolidated sands hosting valuable heavy minerals, mainly ilmenite, rutile, leucoxene and zircon. The large difference in the mineral densities can result in the heavy minerals segregation in the drilling rods causing a biased composition of the recovered samples; • the mineral sands deposits are commonly mined using dredging technologies. The heterogeneous nature and highly variable geotechnical characteristics, including presence of the hard pan lenses within nonconsolidated sediments, imposes an additional challenge on the drilling and mining equipment; • the product costs depend on mineralogy of the heavy fraction, therefore mineral composition of the heavy fraction needs to be accurately estimated into the block model.