Fingerprinting of South African cement clinkers and gypsum as a tool for cement identification purposes

The final composition of cement is of great importance for both the manufacturer and the consumer, since the behaviour of the cement and its application depend largely on it's composition. The composition of cement in turn, depends heavily on the raw materials, the geological origin thereof and the manufacturing process. In previous research, the major element composition of cement has been well-characterised, but the minor and trace element composition in many cases has not. This investigation is an attempt to analyse some of the materials comprising cement, cement clinker and gypsum, for a suite of trace elements that will provide a unique fingerprint of the final product. It was found that for both the clinker and the gypsum a suite of trace elements can be successfully employed to uniquely characterise the materials. The contribution of such a fingerprint is that it can provide valuable information in the case of a forensic analysis for discrimination purposes and also predict the behaviour of these species with regard to their immobilisation in a cementitious matrix.