Journal of Minerals and Materials Characterization and Engineering, 2020, 8, 353-363 https://www.scirp.org/journal/jmmce ISSN Online: 2327-4085 ISSN Print: 2327-4077 Potential of Some Granites from Foumban (West Region of Cameroon) as Fluxing Materials for Ceramics Njimbouombouo Mouliom Soualiou, Etone Macka Alexandre Dodo, Ondoua Abondo Ebengue Yannick, Che Randy Nangah, Njoya André, Mouncherou Oumar Farouk, Ndigui Billong University of Yaounde I, Yaounde, Cameroon How to cite this paper: Soualiou, N.M., Abstract Dodo, E.M.A., Yannick, O.A.E., Nangah, C.R., André, N., Farouk, M.O. and Billong, This study focuses on the mineralogical, geochemical and petrographic char- N. (2020) Potential of Some Granites from acterization of three granite rock samples (LTP, LTS and LTMB) from Foumban (West Region of Cameroon) as Foumban, West Region of Cameroon. Fusibility tests were carried out on the Fluxing Materials for Ceramics. Journal of Minerals and Materials Characterization samples containing the highest amount of alkali to assess the potential of and Engineering, 8, 353-363. these materials as fluxing admixture for ceramics. The results show that the https://doi.org/10.4236/jmmce.2020.85022 granite consists of alkaline feldspars, notably orthoclase and microcline of Received: July 15, 2020 perthitic micro-texture, plagioclases (in particular albite) and also mafic min- Accepted: August 4, 2020 erals such as amphibole and pyroxene. The quantity of alkali in the samples is Published: August 7, 2020 quite high (16.83% for LTS, 17.08% for LTMB and 18.87% for LTP) com- pared to standard data. Fusibility tests carried out on the samples having the Copyright © 2020 by author(s) and Scientific Research Publishing Inc. highest alkali content (LTMB and LTP) showed that the vitreous phase ap- This work is licensed under the Creative pears between 1050˚C and 1100˚C in these samples when they were heated. Commons Attribution International The Fe2O3 and TiO2 content of LTMB (3.01% and 1.49% respectively) led to a License (CC BY 4.0). http://creativecommons.org/licenses/by/4.0/ brown colour of its fired product. Therefore, based on their composition, Open Access these materials can be used as feldspathic fluxes for the formulation of ce- ramic products. Keywords Feldspars, Granite, Characterization, Fusibility, Ceramics, Foumban, Cameroon 1. Introduction Nowadays, feldspathic minerals are more and more and more sought after be- DOI: 10.4236/jmmce.2020.85022 Aug. 7, 2020 353 J. Minerals and Materials Characterization and Engineering N. M. Soualiou et al. cause of the important role they play in the traditional ceramic industry. These minerals are common in rocks and have found several applications in different industries [1]. Feldspathic fluxes can be used in a wide range of ceramic prod- ucts such as in wall tiles, floor tiles, sanitary ware and glasses [2]. They play the role of degreaser during the firing of shards of glass on the one hand and on the other hand, because of their chemical compositions (rich in K2O and Na2O) promote the formation of a vitreous phase at lower melting temperatures [3]. Consequently, the firing temperature of clay formulations containing a given pro- portion of feldspathic fluxes is considerably reduced, resulting in an energy gain. The world today faces the challenge of a high decrease in the supply of feld- spar from its main mineral deposits making it essential to find alternative sources of feldspar which is the second component of ceramic pastes [4]. In Cameroon, very little work has been carried out to identify the sources of feld- spathic materials that can be used in ceramic formulations. Research in this area has been those of a few authors, carried out on the syenite of Lala, nepheline syenites of Kribi and pegmatite of Penja [5] [6] [7], and on the Dschang feldspar mineral deposit [8]. These authors concluded that these deposits can be ex- ploited as potential sources of feldspar fluxes for applications in the ceramic and glass industry. Granitoids, pegmatites, aplites, alkaline and nepheline syenites are the main known sources of feldspar worldwide. The main sources of these rocks are given in Table 1. Among granitoids, granite constitutes an important source of feldspar [2]; granite exploitation opens up a field of research due to its abundance. The rocky bedrock of Foumban (West Region of Cameroon) consists of vol- canic rocks which, as a result of weathering have led to the establishment of sev- eral clay deposits [9] [10] [11] and of crystalline rocks such as mylonite, gneiss and granites which make up the Mayouom kaolin deposits [12]. The presence of these clay deposits in the area could favour the development of the ceramic in- dustry. However, little work has been done to determine the feldspar content of granite rocks from Foumban and their possible use as fluxing materials for ce- ramics. The aim of this work is to characterise the mineralogical, geochemical, petrographic properties of some granites from Foumban and to study their high temperature properties for their application in ceramic formulations. 2. Experimental 2.1. Sampling The three samples (LTP, LTS and LTMB) studied in this work were collected from Foumban, in locations where the main crystalline rock base lies. The sam- ples were taken from syntectonic granites, which are very rich in alkali feldspar phenocrysts and poor in mafic minerals. These rocks consist of perthitic micro- cline, plagioclases including albite and ferromagnesian biotite and amphibole minerals [13]. Figure 1 shows geological map of the sample collection site lo- cated in Foumban (West Region of Cameroon). DOI: 10.4236/jmmce.2020.85022 354 J. Minerals and Materials Characterization and Engineering N. M. Soualiou et al. 2.2. Characterization For mineralogical and geochemical analysis, the rock samples were crushed to 1 - 5 cm diameter using a hammer, ground in a ball mill and sieved with a 100 µm sieve. Thin sections were prepared for petrographic analysis. Table 1. Main sources of feldspathic raw materials generally used in ceramic formulation (modified after Dondi et al. [2]). Source Code Description Deposit example Coarse-grained plutonic rocks, rich in feldspars and oversaturated in silica (quartz > 20%). Fluxes are Spruce pine, USA; Granitoids GRA mainly recovered from granites (particularly Montebras, France; leuco-granites) with minor granodiorites, Strzeblow, Poland. alkaligranites, and some trondhjemites. Very coarse-grained basement rocks, abundant in Sierras pampeanas, feldspar, which in most cases are acid differentiates Argentina; Black Pegmatites PEG of granitoids (or syenoids). Fluxes come from all Hills, USA; subtypes: plutonic pegmatites, pseudo-pegmatites, Kyrkoberget Finland. meta-pegmatites and pegmatoids. Differentiates of granitoid (or syenoid) rocks with a Botro ai Marmi, fine-grained texture. Some fluxes are commercialised Italy; Shigaraki, Aplites APL as “aplites”, as they exhibit an (apparent) aplitic Japan; Montpelier, texture, e.g. due to rock alteration. USA. Extrusive acid rocks (rhyolite, rhyodacite, dacite, Acid Ahuazotepec, Mexico; comendite) including subvolcanic and hypabyssal volcanics Lozzolo, Italy; RHY types (porphyry). Fluxes are recovered from lavas, and Türkismühle, domes, pyroclastics (cinerite, tuff, ignimbrite, and subvolcanis Germany. perlite) and veins. Silica-undersaturated rocks containing feldspars and Nepheline Blue Mountain, feldspathoids (nepheline, leucite, etc.). Fluxes are syenites Canada; Stjernoy, NSP typically obtained as nepheline syenite or its extrusive and Norway; Lages, equivalent nepheline phonolite, but also ultrapotassic phonolites Brazil. rocks can be utilized. Feldspathic sandstones and conglomerates (and the Florinas, Italy; Feldspathics corresponding unlithified sediments). Fluxes are Carrascal del Río, ARK arenites mostly recovered from arkoses and subarkoses, with Spain; Hirschau, some lithic arkoses as well. Germany. Metamorphic equivalents of previous deposits (e.g. Itapeva, Brazil; gneiss, porphyroid, micaschist, quartzite) mostly in Metamorphics MET Campo Largo, Brazil; the greenschist facies. Fluxes are mainly obtained Robilante, Italy. from phyllites and gneisses. Metasomatic rocks formed through an albitization Menderes, Turkey; process that leads to the formation of almost Albitites ALB Ottana, Italy; monomineralic bodies (albite after plagioclase and Salvezines, France. K-feldspar) under the action of metamorphic fluids. Hydrothermal alteration giving rise to peculiar rock Amakusa, Japan; Epithermal types: porcelain stone, eurite, agalmatolite, pinite, EPI Crocetta, Italy; Gusev, alterations toseki and roseki (in Japanese), dunzi or baidunzi (in Russia. Chinese) including episyenite and sanidinite. Low-melting minerals alternative to feldspars; Alternatives end-of-life materials and byproducts, typically sources feldspar bearing or largely glassy, such as mining residues, waste glasses, and combustion ashes. DOI: 10.4236/jmmce.2020.85022 355 J. Minerals and Materials Characterization and Engineering N. M. Soualiou et al. Figure 1. Geological map of the locality of Foumban showing the locations of the mineral deposits (modified after Mefire et al. [11]). - Mineralogical analysis To determine the mineralogical phases, X-ray diffraction was carried out us- ing a Bruker D8 Advance diffractometer. The spectra were recorded from 2˚ to 70˚ with CuKa radiation, no spin, wavelength ka = 1.5406 Å, and a scan rate of 0.020˚, operating at 40 KV and 25 mA at the Clay, Geochemistry and Sedimen-