Co-existing ilmenite-rutile in biotite-gneiss near bingim terrain, Tafawa Balewa, Bauchi State, Nigeria

                                                              Danbatta, U. A.
                                               Department of Geology, Ahmadu Bello University, Zaria, Nigeria.

ABSTRACT

During field research near Tafawa Balewa, about four-centimeter-sized black nodules were mapped in the granite gneiss metamorphic basement complex of Bingim occurring in-situ. Subsequent laboratory investigations carried out by binocular ore microscopy, X-ray Diffraction (XRD) test, and electron microprobe analysis revealed these nodules to be ilmenite-rutile intergrowths. The examinations carried out have demonstrated that the rutile contains 90-99% TiO_2, while the ilmenite contains  (40-50%) Fe-Ti (about equal amounts of Fe and Ti). In addition, they also contained minor to appreciable amounts of ZnO, Al₂O_3, ZrO₂ and MgO. The ilmenite-rutile nodules are thought to be associated with a localise equilibrium established during amphibolite facies retrograde reactions. As ilmenite and rutile are economically important minerals in the paint, plastic and aerospace industries, their present documentation has contributed to their potential industrial significance as exploitable mineral resources of the study area. The occurrence forms a readily available source of ilmenite and rutile that can easily be mined for industrial utilization after very little processing.