Practical way to quantify minerals from chemical assays at Malmberget iron ore operations – An important tool for the geometallurgical program

•Development of a practical, fast and inexpensive technique to calculate the modal mineralogy from routine chemical assays.•This new technique will be easy to integrate as a routine step to support a mineral processing operation.•An ore classification system was established based on iron mineralogy, iron mineral grades and gangue mineralogy of the ore. This is the first step in establishing a geometallurgical program for the Malmberget iron ore deposit, northern Sweden. Geometallurgy captures geological and metallurgical (processing) information into a spatially-based predictive model of mineral processing characteristics. This paper describes the development of a practical, fast and inexpensive technique to quantify minerals from routine chemical assays. Ore samples and process samples from two different orebodies were used in the process of developing this element to mineral conversion technique that involved electron microprobe (EPMA), X-ray fluorescence (XRF) and SATMAGAN analyses. The method was validated against QEMSCAN analyses. From the calculated modal mineralogy an ore classification system was established based on the iron mineralogy, iron mineral grades and gangue mineralogy to create a preliminary geological/geometallurgical model of the ore. However, in a geometallurgical context the modal composition is not sufficient and the geological model requires information on mineral textures, too.