FOURIER-TRANSFORM RAMAN-SPECTROSCOPY OF KANDITE CLAYS

The Raman spectra of the kandite clay minerals, kaolinite, halloysite, dickite and nacrite, have been measured in the 180-3000 cin-1 region using Fourier transform near-IR Raman spectroscopy. These clays have a very small Raman cross-section and long data collection times were of ten required to obtain good spectra. Each day has its own unique chara cteristic Raman spectrum which enables each kandite to be identified e asily. In contrast, it is quite difficult to distinguish kandite clays by IR spectroscopy. Nacrite and dickite have relatively intense Raman peaks in the 1000-1100 cm-1 region, whereas kaolinite is characterize d by an intense peak at 685 cm-1 and halloysite at 470 cm-1.