Published online by Cambridge University Press: 14 March 2018
The possibility of the identification by X-ray diffraction of montmorillonite and swelling chlorite, in the presence or absence of each other, is discussed. Swelling chlorite or montmorillonite, even in mixture with normal chlorite, but in the absence of mica, can be identified by heating to 500°C with immediate sealing of the tube, or by acid treatment followed by solvation with ethylene glycol. If mica is present, however, only the latter procedure will usually ensure positive identification. The same procedures will differentiate montmorillonite and swelling chlorite in mixture only when normal chlorite is absent.