Comparative Study of Local Mining Methods and Assay of Cassiterite with other Alluvial Mineral Deposits in Kuru-Jantar, Plateau State, Nigeria

This research attempt to investigate and compare the local mining methods of cassiterite in Kuru-Jantar with the view to determine the mean recovery per day using statistical approach, separating the valuable minerals through the gravity and magnetic techniques, determine the grade of cassiterite (tin oxide) with the aid of volumetric and energy dispersive x-ray florescence (XRF) analyses; and determine the percentage composition of metals in cassiterite as well as its associate ores with the aid of (XRF). Sub-surface (lotto) and surface (Hand paddock) mining methods were carried out and the respective recovery from each of the method was subjected to processing, sampling and assaying to determine the quantity, quality (grade) and expected smelter-yield. The mean recoveries per day are 14.48 and 11.28 kg/day for lotto and paddock mining methods respectively. The burretting differential obtained for the lotto and paddock methods are 18.80 – 19.80 and 18.80 – 19.30 respectively while their respective percentage tin metal burretted are 90.40 – 97.83 and 92.51 – 97.80 %. The recoveries from the magnetic and gravity separations are 10.91 kg and 9.06 kg for lotto and paddock methods respectively. The XRF analysis gave 68.69 and 66.462 % Sn respectively for the lotto and paddock while the assaying of other associate minerals are 40.4 % Nb; 26.5 % Fe; 22.3 % Ti; 2.5 % Ta; 2.3 % Sn; and 5.1 % W for the paddock and 37.6 % Nb; 24.8 % Fe; 21.5 % Ti; 2.3% Ta; 5.8 % Sn; and 4.9 % W for lotto. It can be observed that the lotto mining method has the highest recovery per day and hence, gives better recovery than paddock mining method. Lotto mining was found to yield higher grade tin-ore concentrate than the hand paddock mining method in both volumetric and XRF analyses but hand paddock gives higher quantity and more associate minerals. It was also found out that the lotto method is more risky and life threatening than paddock mining while the paddock mining practices render more danger to environment than the lotto mining.