Geochemistry and Mineralogical Evaluation of Quartzite Bearing Kyanite in Kuta, Northwestern Nigeria

Abstract

Kyamite is blue to green triclinic mineral, originated from moderately high pressure and temperature associated with regional metamorphism of politic rocks. Kyanite is associated with minerals like staurolite, andalusite, talc and corundum, and is a member of 1:1 aluminous-silicates. Economic occurrences are of lump massive and lenses with at least 35% content of SiO₂ and 40% Al₂O₃. This present study is necessitated as a result of the industrial applications of kyanite. The Kuta kyanitequartzite form a narrow ridge of about 300 metres high and 6km², it intruded into the country rock of mica-schist. AAS and XRD techniques were employed in the determination of chemical and mineralogical composition of ten representative raw and beneficiated kyanite-quartzite samples. Beneficiation was done by electromagnetic and methylene iodide separation techniques. The combined AAS and XRD analyses results show that Al₂O₃ + SiO₂ constitute 92% and kyanite alone constitute 55% of the beneficiated samples, quartz, mulite and silliminite 45%. Evaluation of the indusrial suitability show inconsistent of the Kuta kyanite with BSI and ASTM standards specification for industrial mineral, it can be use as refractory material based on the alumina content.

Keywords: Geochemistry, Mineralogy, Quartzite, Kyanite, Evaluation.