A Mineralogical Study of Diatomite in Leizhou Peninsula

In this paper diatomite samples taken from the Leizhou Peninsula have beenstudied by chemical analysis, DTA, TG, XRD, IR, SEM and X-ray Energy Spectroscopy.The study shows that the diatomaceous genera and species and their organic contents arevariable with buried depth, from Melosira to Stephanodiscus and then to Cyclotella.Various impurities in the samples, such as quartz, kaolinite and montmorillonite indicatedifferent sedimentary environments. When heated, the diatom would change in shape dueto the phase transformation in which amorphous silica crystallized from disordered opal toordered cristobalite. The temperatures of phase transformation are different for variousdiatorns due to the presence of different impurities and constituents of diatomaceousgenera and species.