ABSTRACT
Crucibles are manufactured from naturally occurring substance in the earth crust - clay, quartzite, chromate, bauxite, graphite etc. All these materials do not occur in their pure form, hence needs some form of treatment before their usage in manufacturing. In this study, the graphite from Bauchi State of Nigeria was beneficiated and characterized. The optimum pulp condition for the floatation using froth floatation method was found to be at, 0.3mls of kerosene, 0.5 mls of turpentine and 0.3 mls of 25% Na2CO3 in 50g of graphite ore with 300 mls of water. It was also found that, the agitation time required for optimum recovery before and after addition of the reagent was 10 minutes and 5 minutes respectively. The carbon content was found to be 82wt % for the beneficiated and 42wt% for the raw sample. The density of the beneficiated sample was found to be 2,250 kg/m3 which closely agrees with the literature value of 2,260 kg/m3. The largest flake size was found to be about 1000μm, which makes it a good material for crucible production. 30kg tar bonded crucible were formed using data from laboratory results earlier carried out. But every effort made to fire the crucible failed. Reasons for the failure could not be ascertained. The use of clay pots as substitute for the conventional saggar in the firing could be responsible due to the low gas permeability of the pots.