Geochemical and mineralogical characteristics of Lithomargic clay types from Awaso Bauxite Deposit, Ghana: implications for possible industrial utilization

Abstract

Geochemical and mineralogical methods were employed in characterizing lithomargic clay types underlying Awaso lateritic bauxite deposit in southwestern Ghana in order to assess their suitability for possible industrial utilization. Representative samples analyzed from the deposit revealed kaolinite and gibbsite as the dominant minerals whilst accessory minerals found included goethite, rutile, biotite and muscovite with quartz conspicuously absent. It is possible to wash and separate most of the gibbsite component, which is prevalent in the > 90μm size fractions. On the basis of the results obtained from chemical and mineralogical analyses as well as diagnostic evaluative analyses, the lithomargic clay types could be exploited in the production of aluminium sulphate (alum) for water purification and alumino-silicate refractory material. The raw clay will however have to be beneficiated in order to optimize grade and recovery.