Physicochemical Characteristics of Feldspar Deposits in Zango Daji, Kogi State Using Geological Methods (Published)
Six rock samples were randomly collected and photographs, locational coordinates and elevation points were taken with appropriate tools and devices. Portions of samples were prepared into thin sections and observed under hand lenses, microscope, tested for hardness and other diagnostic properties. Specific density was also determined. The remaining samples were subjected to geochemical and mineralogical analysis. An average percentage composition of 17.1958 mass % of K2O was obtained which is far greater than its Calcium and Sodium contents, indicating it is a K-feldspar. Geochemical result showed averages of Si2O, Al2O3, K2O, Na2O, CaO, and Fe2O3, contents of 59.54 mass %, 17.83 mass %, 17.19 mass %, 2.33 mass %, 0.08 mass % and 1.60 mass % respectively while mineralogical results revealed it is orthoclase in view of its high alumina content of 17.83 percent. The results showed that the sample specification meets the British International Standard specification. Furthermore, electrical resistivity tomography survey was conducted by setting up Schlumberger Electrode Array to determine the significant resistivity contrast between the feldspar and the compact bedrock in the profile. The resistivity data of eight points were processed into Resists curves after conversion and subjecting the data by inversion with WinResist software to obtain 1 – D and 2 – D maps. Together with results of chemical analyses and vertical electrical sounding, the location map of mineralogical composition of the Oxides were determined. Field and petrographic evidence showed a potential source of gemstones and niobium. The study also revealed the occurrence of feldspar deposit are hosted by granitic and pegmatitic intrusive. The quantum and reserve estimates of both overburden layer and target mineral thickness were determined to be 44.3 ± 2.18 million metric tons and 741,933 ± 132,205 m³ respectively.
Keywords: K-feldspar, pegmatitic-intrusives. spectrometry, unweathered- pegmatites, unweathered-granitics