Microscopical methods are key tools in the assessment of potential raw materials to be used in the production of high-quality cement. This month ICR considers the use of optical microscopy in the determination of the mineral composition of the rocks under investigation.

Assessment of potential raw materials involves many lines of enquiry. The chemical composition, geological variation, accessibility and consistency are essential areas for research. An additional key area is the mineralogical composition of rocks. A certain amount can be deduced from techniques such as X-ray diffraction, but much of the character of rocks can best be assessed using microscopical methods.