Mineralogical analysis of heavy minerals from stream sediments, Nigeria

This report presents the results of heavy media separation and the subsequent optical microscopical and mineralogical characterisation of heavy minerals separated from a suite of twenty eight stream sediment samples from Nigeria. The samples were submitted for analysis by Dr Roger Key (BGS) and his team as part of the Nigerian Geochemical Mapping Technical Assistance Project (NGMTAP) which aims to provide baseline geoscientific information for mineral exploration and environmental management through a study of the distribution of important metallic elements. The present investigation follows an initial, pilot mineralogical study carried out on a suite of seven stream sediments samples (Kemp et al., 2009) which in turn was followed by the analysis of a larger batch of sixty stream sediments (Kemp et al., 2010) from the same project. Both studies sought to determine the hosts for elevated levels of zirconium (Zr) and rare earth elements (REEs) in the stream sediments. Zircon was the only Zr-bearing phase identified by XRD in the stream sediments and monazite the only REE-bearing mineral (Kemp et al. 2009, 2010).