Mineralogical Transformation and Microstructure of the Alluvials Clays

  • Isaac Yannick Bomeni Department of Earth Sciences, University of Dschang
  • Armand Sylvain Ludovic Wouatong Department of Earth Sciences, University of Dschang
  • Francois Ngapgue Department of Civil Engineering, Fotso Victor Institute of Technology
  • Kabeyene Véronique Kamgang Department of Earth Science, Higher Teacher Training College
  • Nathalie Fagel National Institute for Materials Science (NIMS)


Mineralogical transformations and microstructures during the firing alluvial clays from Monoun plain were studied. The firing of clays was carried out in the temperature range from 800 to 1150 oC. Minerals transformation was investigated by X-ray diffraction, polarize stereomicroscopy and scanning electron microscopy (SEM). In the raw materials, typical assemblages with quartz, kaolinite, goethite, anatase, hematite, gibbsite and feldspar were observed. Many neoformed mineral phases were identified with the reaction products including mullite, cristobalite, spinel, amorphous phase which occurred in the high temperature (1050 - 1150 oC) in the fired bricks. The quartz phenocrist with some microlites oxides embedded in few mesostasis glass have been illustrated at 950 oC by stereomicroscopy analysis. At 1150 oC, the vitreous matrix has embedded phenocrist of quartz and other relic minerals. The best temperature for fired alluvial clay brick was discovered between 1050-1150 oC.