Methods of clay mineral analysis using the Agilent Xcalibur Nova X-ray diffractometer

The purpose of this project was to design a working method for analyzing clay minerals on Whitman College’s Agilent Xcalibur Nova single-crystal diffractometer. We experimented with sample preparation, programming and orientation of the diffractometer, and data analysis techniques. We were able to achieve comparable results for oriented samples of clay mineral standards on both the Xcalibur Nova and the Siemens D-500 diffractometer at the Geoanalytical Lab at Washington State University. The most successful method for preparing oriented samples was pipetting the sample directly onto small circular glass coverslips, mounting the coverslips vertically in the sample holder, and collecting a sequence of oriented scans. Additionally, we determined that random air-dried powder samples have the strongest signal relative to background when loaded in 0.7 mm capillary tubes. In the future, standard spikes added to the samples may be useful for correcting peak positions in the final scan.