Focusing on the Mineralogical and Chemical Characteristics of Clays Consumed in the District of Abidjan (Côte D’Ivoire)

Clay materials are natural products widely used in various domains including construction, ceramics,
paper, breeding, pharmaceuticals etc. Clay materials of the quarry of Bingerville (district of Abidjan)
have been characterized by chemical analysis, X-rays diffraction, infrared spectroscopy and thermal
analysis. These materials contain kaolinite (41% - 84%), illite (4% - 10%), quartz (14% - 27%),
goethite (2% - 5%) and small amount of rutile (1%) that are not toxic minerals. They also contain
some heavy metals which are beneficial to human biological activity (cobalt, copper, molybdenum,
zinc) in tiny quantities. Some other heavy metals (lead, cadmium) which are considered as poisonous
for human are present in very low content. The samples characterized by relatively fine grains are
moderately crystallized. Their specific surface area varied from 26 to 43 m2∙g−1. The mineralogical
and physicochemical characteristics of these samples are like ones known for their healing properties.
The consumption by internal way of studied materials, although it may be beneficial, requires a sifting
to remove coarse grains (ϕ > 2 μm) and a previous microbiological control. Chemical analyses
showed that the samples contain many elements as alkalis, heavy metal etc.; some of them are
important for biological activity. Mineralogical analysis show that samples consist mainly of kaolinite,
illite associated with impurities as quartz, goethite and rutile.