Petrographic and Physico-Mechanical Characteristics of Quartzite From the Wolframite Mine in Zumba, North-Central Nigeria. Implications for their use as Construction Materials

Abstract

Quartzite from the wolframite mine in Zumba, North-Central Nigeria was investigated using petrography and physico-mechanical tests. The main aim was to deduce its suitability for use as construction material. Field evidence shows that the quartzite is intrusive into schist and granite and about 138,300 m3 of quartzite has been excavated from pits in the study area and dumped as waste material. Petrographic examination of thin sections of the quartzite of the quartzite under a petrological microscope reveals two textural varieties. These are the fine to medium and coarse-grained varieties and quartz is the most abundant mineral in both varieties. Results of physical tests done on the samples show average porosity of 0.35 % with a range of 1 - 0.5 %, while average water absorption is 0.23 % with a range of 0.1 - 0.5 %. average specific gravity of the sample is 2.75 with a range of 2.7 - 2.8, whereas, average bulk density is 2.82 g/cm3 with a range of 2.60 - 2.67 g/cm3. On the other hand, results of mechanical tests show that compressive, tensile and shear strengths have average values and ranges of 100N/m2 and 98 - 105N/m2; 21.1 N/m2 and 10 - 30 N/m2 and 37 N/m2 and 20 - 60 N/m2 respectively. Generally, the physical and mechanical properties when compared to some international standards indicate that it is very good material for construction purposes such as road stabilizers, aggregates, ornamental stones and building blocks. This therefore implies that mine-waste materials can be converted to exploitable resources and industrial products.