The Impact of Swelling Indices of Sokoto Clays on the Moulding Properties of the Clays in Sand Mixtures was investi- gated. Four clays (labeled A, B, C, D) from different locations in Sokoto state of Nigeria were samp...The Impact of Swelling Indices of Sokoto Clays on the Moulding Properties of the Clays in Sand Mixtures was investi- gated. Four clays (labeled A, B, C, D) from different locations in Sokoto state of Nigeria were sampled. The sampling method was that for each deposit five samples were taken at different positions and then mixed together. At the labora- tory they were washed to remove organic matter and then dried at 110°C in the oven. A laboratory ball mill was used to grind the dried clays. Each of the clay was then sampled for the determination of its swelling index. The determination of the moulding properties of the clays then followed. Only green compression strength, dry compression strength and green permeability, moulding properties were determined. The analysis of the result revealed that clay B has the highest green and dry strength values it had the highest green compression strength of 71.7 KN/m2 and the highest dry com- pression strength of 3225.75 KN/m2. Clay B also has the highest swelling index of 60% and very high degree of expan- siveness when compared to the other three clays. Clay B was followed by clay A with swelling index of 25%;the clay has high green and dry compression strength and a moderate degree of expansiveness. The inability of clay D with swelling index of 40% to be the next clay to clay B which has the highest swelling index of 60% among the four clays in terms of good moulding properties is an indication that high swelling index does not always mean good moulding properties in clay binders.展开更多
Determination of the work index of Gyel-Buruku columbite ore sample in Plateau state, Nigeria, was investigated. The sample of the columbite ore was sourced from Gyel village in Jos East Local Government Area of Plate...Determination of the work index of Gyel-Buruku columbite ore sample in Plateau state, Nigeria, was investigated. The sample of the columbite ore was sourced from Gyel village in Jos East Local Government Area of Plateau state, Nigeria. The “reference ores (granites)” samples were sourced from Jiche and Gurum villages of Plateau state respectively. The reference ores and columbite ore of known weights were ground and pulverized. 80% passing size for the columbite ore, Jiche and Gurum granites samples was obtained at 100 μm sieve size for the feeds and products respectively. The work indexes of reference ores i.e. Jiche and Gurum granites were used to calculate the work index of the Gyel columbite ore sample. The values of 3.42 kWh/ton and 2.72 kWh/ton were obtained respectively for the two different reference granites ores samples used and 3.07 kWh/ton was calculated as their average and determined as the value of the work index of the Gyel-Bukuru columbite ore sample. This work index value obtained for the Gyel-Buruku columbite ore sample lies favourably within the work indexes of 3.94 - 10.81 kWh/ton for columbite minerals sighted in the literatures.展开更多
Clays are among the most essential industrial minerals due to their unique physicochemical properties and versatile usage. This paper used Statistical Package for Social Sciences (SPSS) software to characterize five c...Clays are among the most essential industrial minerals due to their unique physicochemical properties and versatile usage. This paper used Statistical Package for Social Sciences (SPSS) software to characterize five clay deposits for their physical and chemical compositions. The package, was employed to carry out the Analysis of Variance (ANOVA) by Post-Hoctambane multiple comparisons and Kristal Wallis at 5% confidence level for the f- and t-tests respectively. The analysis of variance of the chemical components of the samples by post-hoc (f8, 36 = 52.40, p 8, 37.38 and p 2 and Al2O3. Pearson bivariate correlation statistical tool was also used to establish if significant positive interrelationships exist between the parameters in each site of the clay samples at (p < 0.01 and p < 0.05). The result of the correlation indicates a very significant, strong and positive coefficient p-values above 0.900 between the chemical and physicalproperties. Pearson bivariate correlation coefficient between the chemical and physical parameters of the clay samples indicates very significant, strong and positive correlations with p-values above 0.900 at (p < 0.01 and <0.05). The overall physicochemical results indicate that most of the clay samples will meet the requirements for some industrial applications with minimal processing.展开更多
The comparative beneficiation study of Gyel columbite ore using double stage (magnetic-to-magnetic and magnetic-to-gravity), located in the vicinity of Gyel village in Jos South Local Government Area of Plateau State ...The comparative beneficiation study of Gyel columbite ore using double stage (magnetic-to-magnetic and magnetic-to-gravity), located in the vicinity of Gyel village in Jos South Local Government Area of Plateau State to metallurgical grade was carried out. The ore sample was sourced from 20 different pits each 1.5 × 1.5 × 2 meters deep, 50 meter apart covering a land of 50 hectares. The samples from the 20 pits were crushed, pulverized and homogenized. 200 kg of the homogenized ore sample was used for the experiment and laboratory works. Chemical characterization of the ore sample was carried out using energy dispersive X-ray fluorescence spectrometer (ED-XFR). Single and double stage concentration tests using magnetic and gravity methods were carried out respectively. The results of the chemical analysis of ore sample reveal that, Pit 1 contains 12.26% Nb<sub>2</sub>O<sub>5</sub>, 21.6% Fe<sub>2</sub>O<sub>3</sub>, 36.1% SiO<sub>2</sub>;Pit 20 contains 4.78% Nb<sub>2</sub>O<sub>5</sub>, 19.34% Fe<sub>2</sub>O<sub>3</sub>, 23.96% SiO<sub>2</sub> and the homogenized sample contains 6.71% Nb<sub>2</sub>O<sub>5</sub>, 23.1% Fe<sub>2</sub>O<sub>3</sub> and 27.0% SiO<sub>2</sub> averagely. The liberation study reveals that the niobium of ore can be liberated over a range of sieve size fractions of -355 + 63 μm for the coarse and -63 + 45 μm for the fine particle size fractions. On the basis of this, sieve size fractions of -1400 + 355 μm (as coarse size), -355 + 90 μm (as medium size) and -90 + 45 μm (as fine size) were used for the concentration tests. The concentration test using the double stage processes revealed that the air-floatation followed by rapid magnetic method produced a concentrate with the highest percent assay of 54.48% Nb<sub>2</sub>O<sub>5</sub> with a recovery of 96.53% followed by the rapid-to-rapid magnetic method which produced a concentrate assaying 52.12% Nb<sub>2</sub>O<sub>5</sub> with a recovery of 86.96%. These results meet and surpass the 50% Nb<sub>2</sub>O<sub>5</sub> stipulated as the acceptable metallurgical grade concentrate for niobium metal production in the literature.展开更多
The effects of blending Enugu coal and anthracite on tin smelting using Nigerian Dogo Na Hauwa cassiterite have been studied. The work utilized various blends ranging from 100% to 0% anthracite. The content of the Enu...The effects of blending Enugu coal and anthracite on tin smelting using Nigerian Dogo Na Hauwa cassiterite have been studied. The work utilized various blends ranging from 100% to 0% anthracite. The content of the Enugu coal in the blend varied from 5% to 100%. The various tin metal recovery percentage for each batch of smelting using various blends was noted. Anthracite alone had the highest recovery of 71.90% followed by 5% blend of Enugu with anthracite. The result, however, showed that as the Enugu Coal was increased in the blend, the recovery was also decreasing. This equally affected the quality of tin metal recovered by increasing the grade. The work recommended that since the cost of production is the critical issue, 5% - 15% range of Enugu Coal should be used in preparing blends to bring down the cost of imported anthracite which is put at $906.69 per ton. The use of 15% Enugu coal will result in lowering the cost of imported anthracite by $136.0.展开更多
This work is an investigation of the aqueous corrosion inhibition of Al-Cu-Mg Alloy in acidic medium using extract of Sida acuta (wire weed) plant as corrosion inhibitor at 10%, 20%, 30% and 40% v/v of the extract. Af...This work is an investigation of the aqueous corrosion inhibition of Al-Cu-Mg Alloy in acidic medium using extract of Sida acuta (wire weed) plant as corrosion inhibitor at 10%, 20%, 30% and 40% v/v of the extract. After exposing the alloy to the medium, the results showed that the plant extract inhibited the acid induced corrosion. The presence of Sida acuta plant extract reduces corrosion rate from 0.0012 to 0.0001 MPY and percentage protection increases from 37.42% to 93.63% within a ten-day period with increase in percentage volume of the extract. The result has clearly shown that Sida acuta plant extract can be used as a corrosion inhibitor in the part of chemical plant that is made of Al-Cu-Mg Alloy where acid is used for descaling and cleaning.展开更多
Millions of tons of tailing dump at Rayfield mine in Jos in North Central Plateau state of Nigeria have been found to contain large quantity of columbite. Initial attempts to recover columbite concentrates by local mi...Millions of tons of tailing dump at Rayfield mine in Jos in North Central Plateau state of Nigeria have been found to contain large quantity of columbite. Initial attempts to recover columbite concentrates by local miners and mineral speculators from the columbite rich tailing dump failed due to the ineffective processing route employed. Using cone and quartering sampling method, 0.5 kg of the columbite tailing was obtained for sieve and chemical analyses. 50 kg of <1mm fraction of the sample was subjected to a first stage magnetic concentration in a three poles Dry High Intensity Magnetic Separator (DHMS) that separated the columbite in the third pole. The re-grind of the + 0.355 mm rougher concentrate fraction (containing interlocking columbite) to pass the sieve aperture was treated on the DHMS in the second stage. The rougher concentrate undersize and columbite pre-concentrate of the first stage magnetic separation were then gravity concentrated on the air float machine. The Rayfield tailings and final concentrate were assayed using ED-XRFS to obtain 12.5% and 69.6% Nb2O5, respectively. The recovery and separation efficiency were 77.95% and 77.88% in that order. The magnetic and gravity concentrations were found effective at 77.95% recovery for columbite from the Rayfield tailing dump. This study also provided database for optimum recovery of columbite from tailings of mining sites of similar composition.展开更多
The effect of bitter leaf (Vernonia amygdalina) extract as an inhibitor for aluminium silicon alloy in 0.5 M solution of caustic soda using weight loss method has been investigated. The alloy of composition 9% Si and ...The effect of bitter leaf (Vernonia amygdalina) extract as an inhibitor for aluminium silicon alloy in 0.5 M solution of caustic soda using weight loss method has been investigated. The alloy of composition 9% Si and 91% Al was sand cast at the Foundry Shop of the National Metallurgical Development Centre, Jos, Nigeria. The cast alloy was cut and machined to corrosion coupons and immersed into 0.5 M NaOH solution containing varying inhibitor concentrations (0.1%, 0.2%, 0.3%, 0.5% v/v) within a period of fifteen days. From the result, it was found that the adsorption of Vernonia amygdalina reduced the corrosion rate of this group of alloy in the alkaline medium. The inhibitive action of this plant extract was explained using inhibition efficiency and degree of surface coverage. The most suitable inhibitor concentration was found to be 0.5% with inhibition efficiency of 87%. The mechanism of inhibition is by physical adsorption and the adsorbed molecules of the inhibitor lies on the surface of the alloy blocking the active corrosion sites on the alloy, hence, giving the alloy a higher corrosion resistance in the studied environment.展开更多
In this paper, the refractory properties of clay from Ozanagogo had been studied for possible utilization in refractory production. The clay had a specific gravity of 2.57, linear firing shrinkage of 1.01%, 2.14 g/cm3...In this paper, the refractory properties of clay from Ozanagogo had been studied for possible utilization in refractory production. The clay had a specific gravity of 2.57, linear firing shrinkage of 1.01%, 2.14 g/cm3 bulk density and porosity of 20.4%. A cold crushing strength of 17.48 MN/m2 was obtained with modulus of rupture of 8.28 MN/m2. The thermal shock resistance exceeded 30 cycles and the refractoriness was 1750℃. The sample was analysed for its chemical composition, and it was revealed that it contained 38.07% alumina (Al2O3), 46.00% silica (SiO2) and iron impurities (Fe2O3) of 0.78%. The results generally showed that Ozanagogo clay could be used as a refractory material.展开更多
One of the most important useful and widely abundant industrial minerals in the world is the clay minerals. Their applications in various industries are dependent on their properties. In this study, the mineralogical ...One of the most important useful and widely abundant industrial minerals in the world is the clay minerals. Their applications in various industries are dependent on their properties. In this study, the mineralogical and physico-chemical properties of RahinSho (RC), Major Porter (MP), Wereng camp (WC), Kwi (KC) and Naraguta (NC) clay deposits in Plateau State, Nigeria were investigated to evaluate their potentials for some industrial uses. The x-ray diffraction studies revealed the kaolins as the dominant clay minerals in all the samples. The non-clay minerals found were quartz and muscovite. The chemical analyses by x-ray fluorescence also indicated that the silica (SiO2) values of the samples ranged from (41.20 - 62.26)% while the alumina (Al2O3) range was (17.25 - 37.15)%. Some considerable amounts of impurities found were Fe2O3 (0.43 - 27.52)%, TiO2 (0.05 - 3.28)%, K2O (0.13 - 3.01)%. The oxides of Na, Ca and Mg were within acceptable limits in the clays for most purposes. The loss on ignition ranged from 4.30% - 12.43%. The physical properties investigated were particle size distribution that contained heavy clay-size materials ranging from 67.88% - 91.88%, plasticity index had range of values from 15.90% - 33.68%, and drying and firing shrinkages were 1.10% - 2.22% and 1.65% - 4.49% respectively. All the samples attained a temperature of 1500°C without fusion except Naraguta clay that fused at 1300°C. At the temperature of 1200°C, RC, MP and WC clays retained their natural colours of white and near-white respectively, while KC and NC clays changed colours from orange pink and light brown to moderate pink and moderate reddish brown respectively. These results compare very well with several clays elsewhere. Based on these characteristics, the clays were observed to be potentially suitable for the production of paints, tiles, ceramics, refractories, sanitary wares and clay bricks. Minimal processing will increase the potential of RC and MP to meet up with specification for paper, fertilizer and/or pharmaceutical uses.展开更多
文摘The Impact of Swelling Indices of Sokoto Clays on the Moulding Properties of the Clays in Sand Mixtures was investi- gated. Four clays (labeled A, B, C, D) from different locations in Sokoto state of Nigeria were sampled. The sampling method was that for each deposit five samples were taken at different positions and then mixed together. At the labora- tory they were washed to remove organic matter and then dried at 110°C in the oven. A laboratory ball mill was used to grind the dried clays. Each of the clay was then sampled for the determination of its swelling index. The determination of the moulding properties of the clays then followed. Only green compression strength, dry compression strength and green permeability, moulding properties were determined. The analysis of the result revealed that clay B has the highest green and dry strength values it had the highest green compression strength of 71.7 KN/m2 and the highest dry com- pression strength of 3225.75 KN/m2. Clay B also has the highest swelling index of 60% and very high degree of expan- siveness when compared to the other three clays. Clay B was followed by clay A with swelling index of 25%;the clay has high green and dry compression strength and a moderate degree of expansiveness. The inability of clay D with swelling index of 40% to be the next clay to clay B which has the highest swelling index of 60% among the four clays in terms of good moulding properties is an indication that high swelling index does not always mean good moulding properties in clay binders.
文摘Determination of the work index of Gyel-Buruku columbite ore sample in Plateau state, Nigeria, was investigated. The sample of the columbite ore was sourced from Gyel village in Jos East Local Government Area of Plateau state, Nigeria. The “reference ores (granites)” samples were sourced from Jiche and Gurum villages of Plateau state respectively. The reference ores and columbite ore of known weights were ground and pulverized. 80% passing size for the columbite ore, Jiche and Gurum granites samples was obtained at 100 μm sieve size for the feeds and products respectively. The work indexes of reference ores i.e. Jiche and Gurum granites were used to calculate the work index of the Gyel columbite ore sample. The values of 3.42 kWh/ton and 2.72 kWh/ton were obtained respectively for the two different reference granites ores samples used and 3.07 kWh/ton was calculated as their average and determined as the value of the work index of the Gyel-Bukuru columbite ore sample. This work index value obtained for the Gyel-Buruku columbite ore sample lies favourably within the work indexes of 3.94 - 10.81 kWh/ton for columbite minerals sighted in the literatures.
文摘Clays are among the most essential industrial minerals due to their unique physicochemical properties and versatile usage. This paper used Statistical Package for Social Sciences (SPSS) software to characterize five clay deposits for their physical and chemical compositions. The package, was employed to carry out the Analysis of Variance (ANOVA) by Post-Hoctambane multiple comparisons and Kristal Wallis at 5% confidence level for the f- and t-tests respectively. The analysis of variance of the chemical components of the samples by post-hoc (f8, 36 = 52.40, p 8, 37.38 and p 2 and Al2O3. Pearson bivariate correlation statistical tool was also used to establish if significant positive interrelationships exist between the parameters in each site of the clay samples at (p < 0.01 and p < 0.05). The result of the correlation indicates a very significant, strong and positive coefficient p-values above 0.900 between the chemical and physicalproperties. Pearson bivariate correlation coefficient between the chemical and physical parameters of the clay samples indicates very significant, strong and positive correlations with p-values above 0.900 at (p < 0.01 and <0.05). The overall physicochemical results indicate that most of the clay samples will meet the requirements for some industrial applications with minimal processing.
文摘The comparative beneficiation study of Gyel columbite ore using double stage (magnetic-to-magnetic and magnetic-to-gravity), located in the vicinity of Gyel village in Jos South Local Government Area of Plateau State to metallurgical grade was carried out. The ore sample was sourced from 20 different pits each 1.5 × 1.5 × 2 meters deep, 50 meter apart covering a land of 50 hectares. The samples from the 20 pits were crushed, pulverized and homogenized. 200 kg of the homogenized ore sample was used for the experiment and laboratory works. Chemical characterization of the ore sample was carried out using energy dispersive X-ray fluorescence spectrometer (ED-XFR). Single and double stage concentration tests using magnetic and gravity methods were carried out respectively. The results of the chemical analysis of ore sample reveal that, Pit 1 contains 12.26% Nb<sub>2</sub>O<sub>5</sub>, 21.6% Fe<sub>2</sub>O<sub>3</sub>, 36.1% SiO<sub>2</sub>;Pit 20 contains 4.78% Nb<sub>2</sub>O<sub>5</sub>, 19.34% Fe<sub>2</sub>O<sub>3</sub>, 23.96% SiO<sub>2</sub> and the homogenized sample contains 6.71% Nb<sub>2</sub>O<sub>5</sub>, 23.1% Fe<sub>2</sub>O<sub>3</sub> and 27.0% SiO<sub>2</sub> averagely. The liberation study reveals that the niobium of ore can be liberated over a range of sieve size fractions of -355 + 63 μm for the coarse and -63 + 45 μm for the fine particle size fractions. On the basis of this, sieve size fractions of -1400 + 355 μm (as coarse size), -355 + 90 μm (as medium size) and -90 + 45 μm (as fine size) were used for the concentration tests. The concentration test using the double stage processes revealed that the air-floatation followed by rapid magnetic method produced a concentrate with the highest percent assay of 54.48% Nb<sub>2</sub>O<sub>5</sub> with a recovery of 96.53% followed by the rapid-to-rapid magnetic method which produced a concentrate assaying 52.12% Nb<sub>2</sub>O<sub>5</sub> with a recovery of 86.96%. These results meet and surpass the 50% Nb<sub>2</sub>O<sub>5</sub> stipulated as the acceptable metallurgical grade concentrate for niobium metal production in the literature.
文摘The effects of blending Enugu coal and anthracite on tin smelting using Nigerian Dogo Na Hauwa cassiterite have been studied. The work utilized various blends ranging from 100% to 0% anthracite. The content of the Enugu coal in the blend varied from 5% to 100%. The various tin metal recovery percentage for each batch of smelting using various blends was noted. Anthracite alone had the highest recovery of 71.90% followed by 5% blend of Enugu with anthracite. The result, however, showed that as the Enugu Coal was increased in the blend, the recovery was also decreasing. This equally affected the quality of tin metal recovered by increasing the grade. The work recommended that since the cost of production is the critical issue, 5% - 15% range of Enugu Coal should be used in preparing blends to bring down the cost of imported anthracite which is put at $906.69 per ton. The use of 15% Enugu coal will result in lowering the cost of imported anthracite by $136.0.
文摘This work is an investigation of the aqueous corrosion inhibition of Al-Cu-Mg Alloy in acidic medium using extract of Sida acuta (wire weed) plant as corrosion inhibitor at 10%, 20%, 30% and 40% v/v of the extract. After exposing the alloy to the medium, the results showed that the plant extract inhibited the acid induced corrosion. The presence of Sida acuta plant extract reduces corrosion rate from 0.0012 to 0.0001 MPY and percentage protection increases from 37.42% to 93.63% within a ten-day period with increase in percentage volume of the extract. The result has clearly shown that Sida acuta plant extract can be used as a corrosion inhibitor in the part of chemical plant that is made of Al-Cu-Mg Alloy where acid is used for descaling and cleaning.
文摘Millions of tons of tailing dump at Rayfield mine in Jos in North Central Plateau state of Nigeria have been found to contain large quantity of columbite. Initial attempts to recover columbite concentrates by local miners and mineral speculators from the columbite rich tailing dump failed due to the ineffective processing route employed. Using cone and quartering sampling method, 0.5 kg of the columbite tailing was obtained for sieve and chemical analyses. 50 kg of <1mm fraction of the sample was subjected to a first stage magnetic concentration in a three poles Dry High Intensity Magnetic Separator (DHMS) that separated the columbite in the third pole. The re-grind of the + 0.355 mm rougher concentrate fraction (containing interlocking columbite) to pass the sieve aperture was treated on the DHMS in the second stage. The rougher concentrate undersize and columbite pre-concentrate of the first stage magnetic separation were then gravity concentrated on the air float machine. The Rayfield tailings and final concentrate were assayed using ED-XRFS to obtain 12.5% and 69.6% Nb2O5, respectively. The recovery and separation efficiency were 77.95% and 77.88% in that order. The magnetic and gravity concentrations were found effective at 77.95% recovery for columbite from the Rayfield tailing dump. This study also provided database for optimum recovery of columbite from tailings of mining sites of similar composition.
文摘The effect of bitter leaf (Vernonia amygdalina) extract as an inhibitor for aluminium silicon alloy in 0.5 M solution of caustic soda using weight loss method has been investigated. The alloy of composition 9% Si and 91% Al was sand cast at the Foundry Shop of the National Metallurgical Development Centre, Jos, Nigeria. The cast alloy was cut and machined to corrosion coupons and immersed into 0.5 M NaOH solution containing varying inhibitor concentrations (0.1%, 0.2%, 0.3%, 0.5% v/v) within a period of fifteen days. From the result, it was found that the adsorption of Vernonia amygdalina reduced the corrosion rate of this group of alloy in the alkaline medium. The inhibitive action of this plant extract was explained using inhibition efficiency and degree of surface coverage. The most suitable inhibitor concentration was found to be 0.5% with inhibition efficiency of 87%. The mechanism of inhibition is by physical adsorption and the adsorbed molecules of the inhibitor lies on the surface of the alloy blocking the active corrosion sites on the alloy, hence, giving the alloy a higher corrosion resistance in the studied environment.
文摘In this paper, the refractory properties of clay from Ozanagogo had been studied for possible utilization in refractory production. The clay had a specific gravity of 2.57, linear firing shrinkage of 1.01%, 2.14 g/cm3 bulk density and porosity of 20.4%. A cold crushing strength of 17.48 MN/m2 was obtained with modulus of rupture of 8.28 MN/m2. The thermal shock resistance exceeded 30 cycles and the refractoriness was 1750℃. The sample was analysed for its chemical composition, and it was revealed that it contained 38.07% alumina (Al2O3), 46.00% silica (SiO2) and iron impurities (Fe2O3) of 0.78%. The results generally showed that Ozanagogo clay could be used as a refractory material.
文摘One of the most important useful and widely abundant industrial minerals in the world is the clay minerals. Their applications in various industries are dependent on their properties. In this study, the mineralogical and physico-chemical properties of RahinSho (RC), Major Porter (MP), Wereng camp (WC), Kwi (KC) and Naraguta (NC) clay deposits in Plateau State, Nigeria were investigated to evaluate their potentials for some industrial uses. The x-ray diffraction studies revealed the kaolins as the dominant clay minerals in all the samples. The non-clay minerals found were quartz and muscovite. The chemical analyses by x-ray fluorescence also indicated that the silica (SiO2) values of the samples ranged from (41.20 - 62.26)% while the alumina (Al2O3) range was (17.25 - 37.15)%. Some considerable amounts of impurities found were Fe2O3 (0.43 - 27.52)%, TiO2 (0.05 - 3.28)%, K2O (0.13 - 3.01)%. The oxides of Na, Ca and Mg were within acceptable limits in the clays for most purposes. The loss on ignition ranged from 4.30% - 12.43%. The physical properties investigated were particle size distribution that contained heavy clay-size materials ranging from 67.88% - 91.88%, plasticity index had range of values from 15.90% - 33.68%, and drying and firing shrinkages were 1.10% - 2.22% and 1.65% - 4.49% respectively. All the samples attained a temperature of 1500°C without fusion except Naraguta clay that fused at 1300°C. At the temperature of 1200°C, RC, MP and WC clays retained their natural colours of white and near-white respectively, while KC and NC clays changed colours from orange pink and light brown to moderate pink and moderate reddish brown respectively. These results compare very well with several clays elsewhere. Based on these characteristics, the clays were observed to be potentially suitable for the production of paints, tiles, ceramics, refractories, sanitary wares and clay bricks. Minimal processing will increase the potential of RC and MP to meet up with specification for paper, fertilizer and/or pharmaceutical uses.
