EFFECT OF PEBBLE SIZE ON GOLD DISTRIBUTION IN THE BANKET SERIES OF THE STRATIGRAPHY IN TARKWAIAN SUPERGROUP

The purpose of this research is to establish the relationship between the gold grades and the various pebble sizes from a mine. This objective was reached by choosing parameters of interest from the logging and sampling data, lithological data and assay data from the mine. These parameters were further processed using Microsoft Excel to plot graph of pebble size against gold grade. In order to build a concrete ground for the analysis, an average gold grade for the various samples used was calculated and compared to the cut-off grade at the Mine which is 0.45g/t. Upon further analysis, it was observed that, gold grade which are considered economically feasible at the mine is associated with the coarse pebbles, which has a diameter range of (5mm-30mm) and those which are considered as waste are associated with the fine pebbles (less than 5mm diameter). Some of these coarser pebbles are not economically feasible, since their average gold grade when calculated falls below the cut-off grade at the mine. The mode of deposition as well as the topography of the medium at the time of deposition of gold determine the gold grade of a reef. The degree of roundness and sorting of the conglomerates associated with mineralization as well as ore dilution within the depositional medium by the pebbly quartzite and quartzite waste account for the fall in gold grade of the reef.