Characterisation of Iron Oxide Pigments from Itakpe Tailings for Use in Construction Materials

This study characterises iron oxide pigments derived from the mineral processing tailings of the Itakpe iron ore plant in Kogi State, North Central Nigeria, and evaluates their suitability for use as colouring agents in construction materials including concrete, ceramic tiles, and paints. Mineral processing tailings at Itakpe contain significant iron oxide mineral phases that are currently stockpiled as waste, and their conversion to marketable pigment products represents both a revenue opportunity and an environmental benefit. Tailings samples are collected and subjected to XRF, XRD, and SEM characterisation to identify the iron oxide mineral assemblage and particle characteristics. Beneficiation by wet magnetic separation and selective leaching is investigated to produce enriched iron oxide fractions with targeted pigment hue. Colour measurement is performed using a spectrophotometer (CIE L*a*b* system) on pigment-incorporated concrete and ceramic tile specimens. Chemical stability of the pigments in alkaline concrete pore solution and under UV exposure is assessed. Tinting strength is compared with commercially imported iron oxide red pigment. Findings confirm goethite, hematite, and magnetite as the primary iron oxide phases, providing potential for red, yellow, and black pigment fractions. After magnetic beneficiation, hematite-rich fractions achieve tinting strength within 80 percent of commercial reference. Keywords: iron oxide pigment, tailings, Itakpe, construction materials, Kogi State.