Preparing homogeneous samples by milling
The “art of milling” consists in turning a laboratory sample into a representative part sample with homogeneous analytical fineness (Figure 1). When selecting a suitable mill and grinding tools it should be taken into account that the material properties to be determined (e.g. heavy metal traces by XRF analysis) are not altered in any way during the sample preparation process. This not only requires a thorough knowledge of the instruments but also some experience in the preparation of different materials. Finally, care should be taken that possible abrasion from the grinding tools does not interfere with the analysis results.