X-Ray Diffraction And IR Spectroscopy Of Three Forms Of Silica And Mine Dusts

Different mixtures of the three polymorphs of silica viz. quartz, cristobalite and tridymite are analyzed by x-ray diffraction (XRD) and their IR spectra are investigated by photoacoustic spectroscopy. It is observed that XRD provides a higher resolution to distinguish between the three polymorphs in a sample than IR spectroscopy. In the latter, a sharp band near 617 cm-1 is characteristic of both cristobalite and tridymite. A mine dust sample is quantitatively analyzed by XRD and it is shown to contain illite, quartz, kaolinite and calcite.